+/* $OpenBSD: channels.c,v 1.302 2010/01/26 01:28:35 djm Exp $ */
/*
- *
- * channels.c
- *
* Author: Tatu Ylonen <ylo@cs.hut.fi>
- *
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
- *
- * Created: Fri Mar 24 16:35:24 1995 ylo
- *
* This file contains functions for generic socket connection forwarding.
* There is also code for initiating connection forwarding for X11 connections,
* arbitrary tcp/ip connections, and the authentication agent connection.
*
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose. Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
+ *
* SSH2 support added by Markus Friedl.
+ * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
+ * Copyright (c) 1999 Dug Song. All rights reserved.
+ * Copyright (c) 1999 Theo de Raadt. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "includes.h"
-RCSID("$OpenBSD: channels.c,v 1.63 2000/06/25 20:17:57 provos Exp $");
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/un.h>
+#include <sys/socket.h>
+#ifdef HAVE_SYS_TIME_H
+# include <sys/time.h>
+#endif
+
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <termios.h>
+#include <unistd.h>
+#include <stdarg.h>
+
+#include "openbsd-compat/sys-queue.h"
+#include "xmalloc.h"
#include "ssh.h"
+#include "ssh1.h"
+#include "ssh2.h"
#include "packet.h"
-#include "xmalloc.h"
+#include "log.h"
+#include "misc.h"
#include "buffer.h"
-#include "authfd.h"
-#include "uidswap.h"
-#include "readconf.h"
-#include "servconf.h"
-
#include "channels.h"
-#include "nchan.h"
#include "compat.h"
+#include "canohost.h"
+#include "key.h"
+#include "authfd.h"
+#include "pathnames.h"
-#include "ssh2.h"
-
-/* Maximum number of fake X11 displays to try. */
-#define MAX_DISPLAYS 1000
-
-/* Max len of agent socket */
-#define MAX_SOCKET_NAME 100
-
-/* default window/packet sizes for tcp/x11-fwd-channel */
-#define CHAN_TCP_WINDOW_DEFAULT (8*1024)
-#define CHAN_TCP_PACKET_DEFAULT (CHAN_TCP_WINDOW_DEFAULT/2)
-#define CHAN_X11_WINDOW_DEFAULT (4*1024)
-#define CHAN_X11_PACKET_DEFAULT (CHAN_X11_WINDOW_DEFAULT/2)
+/* -- channel core */
/*
* Pointer to an array containing all allocated channels. The array is
* dynamically extended as needed.
*/
-static Channel *channels = NULL;
+static Channel **channels = NULL;
/*
* Size of the channel array. All slots of the array must always be
- * initialized (at least the type field); unused slots are marked with type
- * SSH_CHANNEL_FREE.
+ * initialized (at least the type field); unused slots set to NULL
*/
-static int channels_alloc = 0;
+static u_int channels_alloc = 0;
/*
* Maximum file descriptor value used in any of the channels. This is
- * updated in channel_allocate.
+ * updated in channel_new.
*/
-static int channel_max_fd_value = 0;
+static int channel_max_fd = 0;
-/* Name and directory of socket for authentication agent forwarding. */
-static char *channel_forwarded_auth_socket_name = NULL;
-static char *channel_forwarded_auth_socket_dir = NULL;
-/* Saved X11 authentication protocol name. */
-char *x11_saved_proto = NULL;
-
-/* Saved X11 authentication data. This is the real data. */
-char *x11_saved_data = NULL;
-unsigned int x11_saved_data_len = 0;
-
-/*
- * Fake X11 authentication data. This is what the server will be sending us;
- * we should replace any occurrences of this by the real data.
- */
-char *x11_fake_data = NULL;
-unsigned int x11_fake_data_len;
+/* -- tcp forwarding */
/*
* Data structure for storing which hosts are permitted for forward requests.
u_short listen_port; /* Remote side should listen port number. */
} ForwardPermission;
-/* List of all permitted host/port pairs to connect. */
+/* List of all permitted host/port pairs to connect by the user. */
static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
-/* Number of permitted host/port pairs in the array. */
+
+/* List of all permitted host/port pairs to connect by the admin. */
+static ForwardPermission permitted_adm_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
+
+/* Number of permitted host/port pairs in the array permitted by the user. */
static int num_permitted_opens = 0;
+
+/* Number of permitted host/port pair in the array permitted by the admin. */
+static int num_adm_permitted_opens = 0;
+
/*
* If this is true, all opens are permitted. This is the case on the server
* on which we have to trust the client anyway, and the user could do
*/
static int all_opens_permitted = 0;
-/* This is set to true if both sides support SSH_PROTOFLAG_HOST_IN_FWD_OPEN. */
-static int have_hostname_in_open = 0;
-/* Sets specific protocol options. */
+/* -- X11 forwarding */
-void
-channel_set_options(int hostname_in_open)
-{
- have_hostname_in_open = hostname_in_open;
-}
+/* Maximum number of fake X11 displays to try. */
+#define MAX_DISPLAYS 1000
+
+/* Saved X11 local (client) display. */
+static char *x11_saved_display = NULL;
+
+/* Saved X11 authentication protocol name. */
+static char *x11_saved_proto = NULL;
+
+/* Saved X11 authentication data. This is the real data. */
+static char *x11_saved_data = NULL;
+static u_int x11_saved_data_len = 0;
/*
- * Permits opening to any host/port in SSH_MSG_PORT_OPEN. This is usually
- * called by the server, because the user could connect to any port anyway,
- * and the server has no way to know but to trust the client anyway.
+ * Fake X11 authentication data. This is what the server will be sending us;
+ * we should replace any occurrences of this by the real data.
*/
+static u_char *x11_fake_data = NULL;
+static u_int x11_fake_data_len;
-void
-channel_permit_all_opens()
-{
- all_opens_permitted = 1;
-}
-/* lookup channel by id */
+/* -- agent forwarding */
+
+#define NUM_SOCKS 10
+
+/* AF_UNSPEC or AF_INET or AF_INET6 */
+static int IPv4or6 = AF_UNSPEC;
+
+/* helper */
+static void port_open_helper(Channel *c, char *rtype);
+
+/* non-blocking connect helpers */
+static int connect_next(struct channel_connect *);
+static void channel_connect_ctx_free(struct channel_connect *);
+
+/* -- channel core */
Channel *
-channel_lookup(int id)
+channel_by_id(int id)
{
Channel *c;
- if (id < 0 || id > channels_alloc) {
- log("channel_lookup: %d: bad id", id);
+
+ if (id < 0 || (u_int)id >= channels_alloc) {
+ logit("channel_by_id: %d: bad id", id);
return NULL;
}
- c = &channels[id];
- if (c->type == SSH_CHANNEL_FREE) {
- log("channel_lookup: %d: bad id: channel free", id);
+ c = channels[id];
+ if (c == NULL) {
+ logit("channel_by_id: %d: bad id: channel free", id);
return NULL;
}
return c;
}
+/*
+ * Returns the channel if it is allowed to receive protocol messages.
+ * Private channels, like listening sockets, may not receive messages.
+ */
+Channel *
+channel_lookup(int id)
+{
+ Channel *c;
+
+ if ((c = channel_by_id(id)) == NULL)
+ return (NULL);
+
+ switch (c->type) {
+ case SSH_CHANNEL_X11_OPEN:
+ case SSH_CHANNEL_LARVAL:
+ case SSH_CHANNEL_CONNECTING:
+ case SSH_CHANNEL_DYNAMIC:
+ case SSH_CHANNEL_OPENING:
+ case SSH_CHANNEL_OPEN:
+ case SSH_CHANNEL_INPUT_DRAINING:
+ case SSH_CHANNEL_OUTPUT_DRAINING:
+ return (c);
+ }
+ logit("Non-public channel %d, type %d.", id, c->type);
+ return (NULL);
+}
+
/*
* Register filedescriptors for a channel, used when allocating a channel or
* when the channel consumer/producer is ready, e.g. shell exec'd
*/
-
-void
-channel_register_fds(Channel *c, int rfd, int wfd, int efd, int extusage)
+static void
+channel_register_fds(Channel *c, int rfd, int wfd, int efd,
+ int extusage, int nonblock, int is_tty)
{
/* Update the maximum file descriptor value. */
- if (rfd > channel_max_fd_value)
- channel_max_fd_value = rfd;
- if (wfd > channel_max_fd_value)
- channel_max_fd_value = wfd;
- if (efd > channel_max_fd_value)
- channel_max_fd_value = efd;
- /* XXX set close-on-exec -markus */
+ channel_max_fd = MAX(channel_max_fd, rfd);
+ channel_max_fd = MAX(channel_max_fd, wfd);
+ channel_max_fd = MAX(channel_max_fd, efd);
+
+ if (rfd != -1)
+ fcntl(rfd, F_SETFD, FD_CLOEXEC);
+ if (wfd != -1 && wfd != rfd)
+ fcntl(wfd, F_SETFD, FD_CLOEXEC);
+ if (efd != -1 && efd != rfd && efd != wfd)
+ fcntl(efd, F_SETFD, FD_CLOEXEC);
c->rfd = rfd;
c->wfd = wfd;
c->sock = (rfd == wfd) ? rfd : -1;
c->efd = efd;
c->extended_usage = extusage;
- if (rfd != -1)
- set_nonblock(rfd);
- if (wfd != -1)
- set_nonblock(wfd);
- if (efd != -1)
- set_nonblock(efd);
+
+ if ((c->isatty = is_tty) != 0)
+ debug2("channel %d: rfd %d isatty", c->self, c->rfd);
+ c->wfd_isatty = is_tty || isatty(c->wfd);
+
+ /* enable nonblocking mode */
+ if (nonblock) {
+ if (rfd != -1)
+ set_nonblock(rfd);
+ if (wfd != -1)
+ set_nonblock(wfd);
+ if (efd != -1)
+ set_nonblock(efd);
+ }
}
/*
* Allocate a new channel object and set its type and socket. This will cause
* remote_name to be freed.
*/
-
-int
+Channel *
channel_new(char *ctype, int type, int rfd, int wfd, int efd,
- int window, int maxpack, int extusage, char *remote_name)
+ u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
{
- int i, found;
+ int found;
+ u_int i;
Channel *c;
/* Do initial allocation if this is the first call. */
if (channels_alloc == 0) {
- chan_init();
channels_alloc = 10;
- channels = xmalloc(channels_alloc * sizeof(Channel));
+ channels = xcalloc(channels_alloc, sizeof(Channel *));
for (i = 0; i < channels_alloc; i++)
- channels[i].type = SSH_CHANNEL_FREE;
- /*
- * Kludge: arrange a call to channel_stop_listening if we
- * terminate with fatal().
- */
- fatal_add_cleanup((void (*) (void *)) channel_stop_listening, NULL);
+ channels[i] = NULL;
}
/* Try to find a free slot where to put the new channel. */
for (found = -1, i = 0; i < channels_alloc; i++)
- if (channels[i].type == SSH_CHANNEL_FREE) {
+ if (channels[i] == NULL) {
/* Found a free slot. */
- found = i;
+ found = (int)i;
break;
}
- if (found == -1) {
+ if (found < 0) {
/* There are no free slots. Take last+1 slot and expand the array. */
found = channels_alloc;
+ if (channels_alloc > 10000)
+ fatal("channel_new: internal error: channels_alloc %d "
+ "too big.", channels_alloc);
+ channels = xrealloc(channels, channels_alloc + 10,
+ sizeof(Channel *));
channels_alloc += 10;
- debug("channel: expanding %d", channels_alloc);
- channels = xrealloc(channels, channels_alloc * sizeof(Channel));
+ debug2("channel: expanding %d", channels_alloc);
for (i = found; i < channels_alloc; i++)
- channels[i].type = SSH_CHANNEL_FREE;
+ channels[i] = NULL;
}
- /* Initialize and return new channel number. */
- c = &channels[found];
+ /* Initialize and return new channel. */
+ c = channels[found] = xcalloc(1, sizeof(Channel));
buffer_init(&c->input);
buffer_init(&c->output);
buffer_init(&c->extended);
- chan_init_iostates(c);
- channel_register_fds(c, rfd, wfd, efd, extusage);
+ c->path = NULL;
+ c->ostate = CHAN_OUTPUT_OPEN;
+ c->istate = CHAN_INPUT_OPEN;
+ c->flags = 0;
+ channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, 0);
c->self = found;
c->type = type;
c->ctype = ctype;
c->local_consumed = 0;
c->local_maxpacket = maxpack;
c->remote_id = -1;
- c->remote_name = remote_name;
+ c->remote_name = xstrdup(remote_name);
c->remote_window = 0;
c->remote_maxpacket = 0;
- c->cb_fn = NULL;
- c->cb_arg = NULL;
- c->cb_event = 0;
- c->dettach_user = NULL;
+ c->force_drain = 0;
+ c->single_connection = 0;
+ c->detach_user = NULL;
+ c->detach_close = 0;
+ c->open_confirm = NULL;
+ c->open_confirm_ctx = NULL;
+ c->input_filter = NULL;
+ c->output_filter = NULL;
+ c->filter_ctx = NULL;
+ c->filter_cleanup = NULL;
+ c->ctl_chan = -1;
+ c->mux_rcb = NULL;
+ c->mux_ctx = NULL;
+ c->delayed = 1; /* prevent call to channel_post handler */
+ TAILQ_INIT(&c->status_confirms);
debug("channel %d: new [%s]", found, remote_name);
- return found;
+ return c;
}
-/* old interface XXX */
-int
-channel_allocate(int type, int sock, char *remote_name)
+
+static int
+channel_find_maxfd(void)
{
- return channel_new("", type, sock, sock, -1, 0, 0, 0, remote_name);
+ u_int i;
+ int max = 0;
+ Channel *c;
+
+ for (i = 0; i < channels_alloc; i++) {
+ c = channels[i];
+ if (c != NULL) {
+ max = MAX(max, c->rfd);
+ max = MAX(max, c->wfd);
+ max = MAX(max, c->efd);
+ }
+ }
+ return max;
}
+int
+channel_close_fd(int *fdp)
+{
+ int ret = 0, fd = *fdp;
-/* Close all channel fd/socket. */
+ if (fd != -1) {
+ ret = close(fd);
+ *fdp = -1;
+ if (fd == channel_max_fd)
+ channel_max_fd = channel_find_maxfd();
+ }
+ return ret;
+}
-void
+/* Close all channel fd/socket. */
+static void
channel_close_fds(Channel *c)
{
- if (c->sock != -1) {
- close(c->sock);
- c->sock = -1;
- }
- if (c->rfd != -1) {
- close(c->rfd);
- c->rfd = -1;
- }
- if (c->wfd != -1) {
- close(c->wfd);
- c->wfd = -1;
- }
- if (c->efd != -1) {
- close(c->efd);
- c->efd = -1;
- }
+ debug3("channel %d: close_fds r %d w %d e %d",
+ c->self, c->rfd, c->wfd, c->efd);
+
+ channel_close_fd(&c->sock);
+ channel_close_fd(&c->rfd);
+ channel_close_fd(&c->wfd);
+ channel_close_fd(&c->efd);
}
/* Free the channel and close its fd/socket. */
-
void
-channel_free(int id)
+channel_free(Channel *c)
{
- Channel *c = channel_lookup(id);
- if (c == NULL)
- packet_disconnect("channel free: bad local channel %d", id);
- debug("channel_free: channel %d: status: %s", id, channel_open_message());
- if (c->dettach_user != NULL) {
- debug("channel_free: channel %d: dettaching channel user", id);
- c->dettach_user(c->self, NULL);
- }
+ char *s;
+ u_int i, n;
+ struct channel_confirm *cc;
+
+ for (n = 0, i = 0; i < channels_alloc; i++)
+ if (channels[i])
+ n++;
+ debug("channel %d: free: %s, nchannels %u", c->self,
+ c->remote_name ? c->remote_name : "???", n);
+
+ s = channel_open_message();
+ debug3("channel %d: status: %s", c->self, s);
+ xfree(s);
+
if (c->sock != -1)
shutdown(c->sock, SHUT_RDWR);
channel_close_fds(c);
buffer_free(&c->input);
buffer_free(&c->output);
buffer_free(&c->extended);
- c->type = SSH_CHANNEL_FREE;
if (c->remote_name) {
xfree(c->remote_name);
c->remote_name = NULL;
}
+ if (c->path) {
+ xfree(c->path);
+ c->path = NULL;
+ }
+ while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
+ if (cc->abandon_cb != NULL)
+ cc->abandon_cb(c, cc->ctx);
+ TAILQ_REMOVE(&c->status_confirms, cc, entry);
+ bzero(cc, sizeof(*cc));
+ xfree(cc);
+ }
+ if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
+ c->filter_cleanup(c->self, c->filter_ctx);
+ channels[c->self] = NULL;
+ xfree(c);
}
-/*
- * 'channel_pre*' are called just before select() to add any bits relevant to
- * channels in the select bitmasks.
- */
-/*
- * 'channel_post*': perform any appropriate operations for channels which
- * have events pending.
- */
-typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset);
-chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
-chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
-
void
-channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset)
+channel_free_all(void)
{
- FD_SET(c->sock, readset);
+ u_int i;
+
+ for (i = 0; i < channels_alloc; i++)
+ if (channels[i] != NULL)
+ channel_free(channels[i]);
}
+/*
+ * Closes the sockets/fds of all channels. This is used to close extra file
+ * descriptors after a fork.
+ */
void
-channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset)
+channel_close_all(void)
{
- if (buffer_len(&c->input) < packet_get_maxsize())
- FD_SET(c->sock, readset);
- if (buffer_len(&c->output) > 0)
- FD_SET(c->sock, writeset);
+ u_int i;
+
+ for (i = 0; i < channels_alloc; i++)
+ if (channels[i] != NULL)
+ channel_close_fds(channels[i]);
}
+/*
+ * Stop listening to channels.
+ */
void
-channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset)
+channel_stop_listening(void)
{
- /* test whether sockets are 'alive' for read/write */
- if (c->istate == CHAN_INPUT_OPEN)
- if (buffer_len(&c->input) < packet_get_maxsize())
- FD_SET(c->sock, readset);
- if (c->ostate == CHAN_OUTPUT_OPEN ||
- c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
- if (buffer_len(&c->output) > 0) {
- FD_SET(c->sock, writeset);
- } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
- chan_obuf_empty(c);
+ u_int i;
+ Channel *c;
+
+ for (i = 0; i < channels_alloc; i++) {
+ c = channels[i];
+ if (c != NULL) {
+ switch (c->type) {
+ case SSH_CHANNEL_AUTH_SOCKET:
+ case SSH_CHANNEL_PORT_LISTENER:
+ case SSH_CHANNEL_RPORT_LISTENER:
+ case SSH_CHANNEL_X11_LISTENER:
+ channel_close_fd(&c->sock);
+ channel_free(c);
+ break;
+ }
}
}
}
-void
-channel_pre_open_20(Channel *c, fd_set * readset, fd_set * writeset)
+/*
+ * Returns true if no channel has too much buffered data, and false if one or
+ * more channel is overfull.
+ */
+int
+channel_not_very_much_buffered_data(void)
{
- if (c->istate == CHAN_INPUT_OPEN &&
- c->remote_window > 0 &&
- buffer_len(&c->input) < c->remote_window)
- FD_SET(c->rfd, readset);
- if (c->ostate == CHAN_OUTPUT_OPEN ||
- c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
- if (buffer_len(&c->output) > 0) {
- FD_SET(c->wfd, writeset);
- } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
- chan_obuf_empty(c);
+ u_int i;
+ Channel *c;
+
+ for (i = 0; i < channels_alloc; i++) {
+ c = channels[i];
+ if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
+#if 0
+ if (!compat20 &&
+ buffer_len(&c->input) > packet_get_maxsize()) {
+ debug2("channel %d: big input buffer %d",
+ c->self, buffer_len(&c->input));
+ return 0;
+ }
+#endif
+ if (buffer_len(&c->output) > packet_get_maxsize()) {
+ debug2("channel %d: big output buffer %u > %u",
+ c->self, buffer_len(&c->output),
+ packet_get_maxsize());
+ return 0;
+ }
}
}
- /** XXX check close conditions, too */
- if (c->efd != -1) {
- if (c->extended_usage == CHAN_EXTENDED_WRITE &&
- buffer_len(&c->extended) > 0)
- FD_SET(c->efd, writeset);
- else if (c->extended_usage == CHAN_EXTENDED_READ &&
- buffer_len(&c->extended) < c->remote_window)
- FD_SET(c->efd, readset);
- }
+ return 1;
}
-void
-channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset)
+/* Returns true if any channel is still open. */
+int
+channel_still_open(void)
{
- if (buffer_len(&c->input) == 0) {
- packet_start(SSH_MSG_CHANNEL_CLOSE);
- packet_put_int(c->remote_id);
- packet_send();
- c->type = SSH_CHANNEL_CLOSED;
- debug("Closing channel %d after input drain.", c->self);
+ u_int i;
+ Channel *c;
+
+ for (i = 0; i < channels_alloc; i++) {
+ c = channels[i];
+ if (c == NULL)
+ continue;
+ switch (c->type) {
+ case SSH_CHANNEL_X11_LISTENER:
+ case SSH_CHANNEL_PORT_LISTENER:
+ case SSH_CHANNEL_RPORT_LISTENER:
+ case SSH_CHANNEL_MUX_LISTENER:
+ case SSH_CHANNEL_CLOSED:
+ case SSH_CHANNEL_AUTH_SOCKET:
+ case SSH_CHANNEL_DYNAMIC:
+ case SSH_CHANNEL_CONNECTING:
+ case SSH_CHANNEL_ZOMBIE:
+ continue;
+ case SSH_CHANNEL_LARVAL:
+ if (!compat20)
+ fatal("cannot happen: SSH_CHANNEL_LARVAL");
+ continue;
+ case SSH_CHANNEL_OPENING:
+ case SSH_CHANNEL_OPEN:
+ case SSH_CHANNEL_X11_OPEN:
+ case SSH_CHANNEL_MUX_CLIENT:
+ return 1;
+ case SSH_CHANNEL_INPUT_DRAINING:
+ case SSH_CHANNEL_OUTPUT_DRAINING:
+ if (!compat13)
+ fatal("cannot happen: OUT_DRAIN");
+ return 1;
+ default:
+ fatal("channel_still_open: bad channel type %d", c->type);
+ /* NOTREACHED */
+ }
}
+ return 0;
}
-void
-channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
+/* Returns the id of an open channel suitable for keepaliving */
+int
+channel_find_open(void)
{
- if (buffer_len(&c->output) == 0)
- channel_free(c->self);
- else
- FD_SET(c->sock, writeset);
+ u_int i;
+ Channel *c;
+
+ for (i = 0; i < channels_alloc; i++) {
+ c = channels[i];
+ if (c == NULL || c->remote_id < 0)
+ continue;
+ switch (c->type) {
+ case SSH_CHANNEL_CLOSED:
+ case SSH_CHANNEL_DYNAMIC:
+ case SSH_CHANNEL_X11_LISTENER:
+ case SSH_CHANNEL_PORT_LISTENER:
+ case SSH_CHANNEL_RPORT_LISTENER:
+ case SSH_CHANNEL_MUX_LISTENER:
+ case SSH_CHANNEL_MUX_CLIENT:
+ case SSH_CHANNEL_OPENING:
+ case SSH_CHANNEL_CONNECTING:
+ case SSH_CHANNEL_ZOMBIE:
+ continue;
+ case SSH_CHANNEL_LARVAL:
+ case SSH_CHANNEL_AUTH_SOCKET:
+ case SSH_CHANNEL_OPEN:
+ case SSH_CHANNEL_X11_OPEN:
+ return i;
+ case SSH_CHANNEL_INPUT_DRAINING:
+ case SSH_CHANNEL_OUTPUT_DRAINING:
+ if (!compat13)
+ fatal("cannot happen: OUT_DRAIN");
+ return i;
+ default:
+ fatal("channel_find_open: bad channel type %d", c->type);
+ /* NOTREACHED */
+ }
+ }
+ return -1;
}
+
/*
- * This is a special state for X11 authentication spoofing. An opened X11
- * connection (when authentication spoofing is being done) remains in this
- * state until the first packet has been completely read. The authentication
- * data in that packet is then substituted by the real data if it matches the
- * fake data, and the channel is put into normal mode.
- * XXX All this happens at the client side.
- */
-int
-x11_open_helper(Channel *c)
+ * Returns a message describing the currently open forwarded connections,
+ * suitable for sending to the client. The message contains crlf pairs for
+ * newlines.
+ */
+char *
+channel_open_message(void)
+{
+ Buffer buffer;
+ Channel *c;
+ char buf[1024], *cp;
+ u_int i;
+
+ buffer_init(&buffer);
+ snprintf(buf, sizeof buf, "The following connections are open:\r\n");
+ buffer_append(&buffer, buf, strlen(buf));
+ for (i = 0; i < channels_alloc; i++) {
+ c = channels[i];
+ if (c == NULL)
+ continue;
+ switch (c->type) {
+ case SSH_CHANNEL_X11_LISTENER:
+ case SSH_CHANNEL_PORT_LISTENER:
+ case SSH_CHANNEL_RPORT_LISTENER:
+ case SSH_CHANNEL_CLOSED:
+ case SSH_CHANNEL_AUTH_SOCKET:
+ case SSH_CHANNEL_ZOMBIE:
+ case SSH_CHANNEL_MUX_CLIENT:
+ case SSH_CHANNEL_MUX_LISTENER:
+ continue;
+ case SSH_CHANNEL_LARVAL:
+ case SSH_CHANNEL_OPENING:
+ case SSH_CHANNEL_CONNECTING:
+ case SSH_CHANNEL_DYNAMIC:
+ case SSH_CHANNEL_OPEN:
+ case SSH_CHANNEL_X11_OPEN:
+ case SSH_CHANNEL_INPUT_DRAINING:
+ case SSH_CHANNEL_OUTPUT_DRAINING:
+ snprintf(buf, sizeof buf,
+ " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cc %d)\r\n",
+ c->self, c->remote_name,
+ c->type, c->remote_id,
+ c->istate, buffer_len(&c->input),
+ c->ostate, buffer_len(&c->output),
+ c->rfd, c->wfd, c->ctl_chan);
+ buffer_append(&buffer, buf, strlen(buf));
+ continue;
+ default:
+ fatal("channel_open_message: bad channel type %d", c->type);
+ /* NOTREACHED */
+ }
+ }
+ buffer_append(&buffer, "\0", 1);
+ cp = xstrdup(buffer_ptr(&buffer));
+ buffer_free(&buffer);
+ return cp;
+}
+
+void
+channel_send_open(int id)
+{
+ Channel *c = channel_lookup(id);
+
+ if (c == NULL) {
+ logit("channel_send_open: %d: bad id", id);
+ return;
+ }
+ debug2("channel %d: send open", id);
+ packet_start(SSH2_MSG_CHANNEL_OPEN);
+ packet_put_cstring(c->ctype);
+ packet_put_int(c->self);
+ packet_put_int(c->local_window);
+ packet_put_int(c->local_maxpacket);
+ packet_send();
+}
+
+void
+channel_request_start(int id, char *service, int wantconfirm)
+{
+ Channel *c = channel_lookup(id);
+
+ if (c == NULL) {
+ logit("channel_request_start: %d: unknown channel id", id);
+ return;
+ }
+ debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
+ packet_start(SSH2_MSG_CHANNEL_REQUEST);
+ packet_put_int(c->remote_id);
+ packet_put_cstring(service);
+ packet_put_char(wantconfirm);
+}
+
+void
+channel_register_status_confirm(int id, channel_confirm_cb *cb,
+ channel_confirm_abandon_cb *abandon_cb, void *ctx)
+{
+ struct channel_confirm *cc;
+ Channel *c;
+
+ if ((c = channel_lookup(id)) == NULL)
+ fatal("channel_register_expect: %d: bad id", id);
+
+ cc = xmalloc(sizeof(*cc));
+ cc->cb = cb;
+ cc->abandon_cb = abandon_cb;
+ cc->ctx = ctx;
+ TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
+}
+
+void
+channel_register_open_confirm(int id, channel_callback_fn *fn, void *ctx)
+{
+ Channel *c = channel_lookup(id);
+
+ if (c == NULL) {
+ logit("channel_register_open_confirm: %d: bad id", id);
+ return;
+ }
+ c->open_confirm = fn;
+ c->open_confirm_ctx = ctx;
+}
+
+void
+channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
+{
+ Channel *c = channel_by_id(id);
+
+ if (c == NULL) {
+ logit("channel_register_cleanup: %d: bad id", id);
+ return;
+ }
+ c->detach_user = fn;
+ c->detach_close = do_close;
+}
+
+void
+channel_cancel_cleanup(int id)
+{
+ Channel *c = channel_by_id(id);
+
+ if (c == NULL) {
+ logit("channel_cancel_cleanup: %d: bad id", id);
+ return;
+ }
+ c->detach_user = NULL;
+ c->detach_close = 0;
+}
+
+void
+channel_register_filter(int id, channel_infilter_fn *ifn,
+ channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
+{
+ Channel *c = channel_lookup(id);
+
+ if (c == NULL) {
+ logit("channel_register_filter: %d: bad id", id);
+ return;
+ }
+ c->input_filter = ifn;
+ c->output_filter = ofn;
+ c->filter_ctx = ctx;
+ c->filter_cleanup = cfn;
+}
+
+void
+channel_set_fds(int id, int rfd, int wfd, int efd,
+ int extusage, int nonblock, int is_tty, u_int window_max)
+{
+ Channel *c = channel_lookup(id);
+
+ if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
+ fatal("channel_activate for non-larval channel %d.", id);
+ channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, is_tty);
+ c->type = SSH_CHANNEL_OPEN;
+ c->local_window = c->local_window_max = window_max;
+ packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
+ packet_put_int(c->remote_id);
+ packet_put_int(c->local_window);
+ packet_send();
+}
+
+/*
+ * 'channel_pre*' are called just before select() to add any bits relevant to
+ * channels in the select bitmasks.
+ */
+/*
+ * 'channel_post*': perform any appropriate operations for channels which
+ * have events pending.
+ */
+typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
+chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
+chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
+
+/* ARGSUSED */
+static void
+channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
+{
+ FD_SET(c->sock, readset);
+}
+
+/* ARGSUSED */
+static void
+channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
+{
+ debug3("channel %d: waiting for connection", c->self);
+ FD_SET(c->sock, writeset);
+}
+
+static void
+channel_pre_open_13(Channel *c, fd_set *readset, fd_set *writeset)
+{
+ if (buffer_len(&c->input) < packet_get_maxsize())
+ FD_SET(c->sock, readset);
+ if (buffer_len(&c->output) > 0)
+ FD_SET(c->sock, writeset);
+}
+
+static void
+channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
+{
+ u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
+
+ if (c->istate == CHAN_INPUT_OPEN &&
+ limit > 0 &&
+ buffer_len(&c->input) < limit &&
+ buffer_check_alloc(&c->input, CHAN_RBUF))
+ FD_SET(c->rfd, readset);
+ if (c->ostate == CHAN_OUTPUT_OPEN ||
+ c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
+ if (buffer_len(&c->output) > 0) {
+ FD_SET(c->wfd, writeset);
+ } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
+ if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
+ debug2("channel %d: obuf_empty delayed efd %d/(%d)",
+ c->self, c->efd, buffer_len(&c->extended));
+ else
+ chan_obuf_empty(c);
+ }
+ }
+ /** XXX check close conditions, too */
+ if (compat20 && c->efd != -1 &&
+ !(c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED)) {
+ if (c->extended_usage == CHAN_EXTENDED_WRITE &&
+ buffer_len(&c->extended) > 0)
+ FD_SET(c->efd, writeset);
+ else if (!(c->flags & CHAN_EOF_SENT) &&
+ c->extended_usage == CHAN_EXTENDED_READ &&
+ buffer_len(&c->extended) < c->remote_window)
+ FD_SET(c->efd, readset);
+ }
+ /* XXX: What about efd? races? */
+}
+
+/* ARGSUSED */
+static void
+channel_pre_input_draining(Channel *c, fd_set *readset, fd_set *writeset)
+{
+ if (buffer_len(&c->input) == 0) {
+ packet_start(SSH_MSG_CHANNEL_CLOSE);
+ packet_put_int(c->remote_id);
+ packet_send();
+ c->type = SSH_CHANNEL_CLOSED;
+ debug2("channel %d: closing after input drain.", c->self);
+ }
+}
+
+/* ARGSUSED */
+static void
+channel_pre_output_draining(Channel *c, fd_set *readset, fd_set *writeset)
{
- unsigned char *ucp;
- unsigned int proto_len, data_len;
+ if (buffer_len(&c->output) == 0)
+ chan_mark_dead(c);
+ else
+ FD_SET(c->sock, writeset);
+}
+
+/*
+ * This is a special state for X11 authentication spoofing. An opened X11
+ * connection (when authentication spoofing is being done) remains in this
+ * state until the first packet has been completely read. The authentication
+ * data in that packet is then substituted by the real data if it matches the
+ * fake data, and the channel is put into normal mode.
+ * XXX All this happens at the client side.
+ * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
+ */
+static int
+x11_open_helper(Buffer *b)
+{
+ u_char *ucp;
+ u_int proto_len, data_len;
/* Check if the fixed size part of the packet is in buffer. */
- if (buffer_len(&c->output) < 12)
+ if (buffer_len(b) < 12)
return 0;
/* Parse the lengths of variable-length fields. */
- ucp = (unsigned char *) buffer_ptr(&c->output);
+ ucp = buffer_ptr(b);
if (ucp[0] == 0x42) { /* Byte order MSB first. */
proto_len = 256 * ucp[6] + ucp[7];
data_len = 256 * ucp[8] + ucp[9];
proto_len = ucp[6] + 256 * ucp[7];
data_len = ucp[8] + 256 * ucp[9];
} else {
- debug("Initial X11 packet contains bad byte order byte: 0x%x",
- ucp[0]);
+ debug2("Initial X11 packet contains bad byte order byte: 0x%x",
+ ucp[0]);
return -1;
}
/* Check if the whole packet is in buffer. */
- if (buffer_len(&c->output) <
+ if (buffer_len(b) <
12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
return 0;
/* Check if authentication protocol matches. */
if (proto_len != strlen(x11_saved_proto) ||
memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
- debug("X11 connection uses different authentication protocol.");
+ debug2("X11 connection uses different authentication protocol.");
return -1;
}
/* Check if authentication data matches our fake data. */
if (data_len != x11_fake_data_len ||
memcmp(ucp + 12 + ((proto_len + 3) & ~3),
x11_fake_data, x11_fake_data_len) != 0) {
- debug("X11 auth data does not match fake data.");
+ debug2("X11 auth data does not match fake data.");
return -1;
}
/* Check fake data length */
return 1;
}
-void
-channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset)
+static void
+channel_pre_x11_open_13(Channel *c, fd_set *readset, fd_set *writeset)
{
- int ret = x11_open_helper(c);
+ int ret = x11_open_helper(&c->output);
+
if (ret == 1) {
/* Start normal processing for the channel. */
c->type = SSH_CHANNEL_OPEN;
* We have received an X11 connection that has bad
* authentication information.
*/
- log("X11 connection rejected because of wrong authentication.\r\n");
+ logit("X11 connection rejected because of wrong authentication.");
buffer_clear(&c->input);
buffer_clear(&c->output);
- close(c->sock);
+ channel_close_fd(&c->sock);
c->sock = -1;
c->type = SSH_CHANNEL_CLOSED;
packet_start(SSH_MSG_CHANNEL_CLOSE);
}
}
-void
-channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset)
+static void
+channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
{
- int ret = x11_open_helper(c);
+ int ret = x11_open_helper(&c->output);
+
+ /* c->force_drain = 1; */
+
if (ret == 1) {
c->type = SSH_CHANNEL_OPEN;
+ channel_pre_open(c, readset, writeset);
+ } else if (ret == -1) {
+ logit("X11 connection rejected because of wrong authentication.");
+ debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
+ chan_read_failed(c);
+ buffer_clear(&c->input);
+ chan_ibuf_empty(c);
+ buffer_clear(&c->output);
+ /* for proto v1, the peer will send an IEOF */
if (compat20)
- channel_pre_open_20(c, readset, writeset);
+ chan_write_failed(c);
else
- channel_pre_open_15(c, readset, writeset);
- } else if (ret == -1) {
- debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
- chan_read_failed(c); /** force close? */
- chan_write_failed(c);
- debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
+ c->type = SSH_CHANNEL_OPEN;
+ debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
+ }
+}
+
+static void
+channel_pre_mux_client(Channel *c, fd_set *readset, fd_set *writeset)
+{
+ if (c->istate == CHAN_INPUT_OPEN &&
+ buffer_check_alloc(&c->input, CHAN_RBUF))
+ FD_SET(c->rfd, readset);
+ if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
+ /* clear buffer immediately (discard any partial packet) */
+ buffer_clear(&c->input);
+ chan_ibuf_empty(c);
+ /* Start output drain. XXX just kill chan? */
+ chan_rcvd_oclose(c);
+ }
+ if (c->ostate == CHAN_OUTPUT_OPEN ||
+ c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
+ if (buffer_len(&c->output) > 0)
+ FD_SET(c->wfd, writeset);
+ else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
+ chan_obuf_empty(c);
+ }
+}
+
+/* try to decode a socks4 header */
+/* ARGSUSED */
+static int
+channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
+{
+ char *p, *host;
+ u_int len, have, i, found, need;
+ char username[256];
+ struct {
+ u_int8_t version;
+ u_int8_t command;
+ u_int16_t dest_port;
+ struct in_addr dest_addr;
+ } s4_req, s4_rsp;
+
+ debug2("channel %d: decode socks4", c->self);
+
+ have = buffer_len(&c->input);
+ len = sizeof(s4_req);
+ if (have < len)
+ return 0;
+ p = buffer_ptr(&c->input);
+
+ need = 1;
+ /* SOCKS4A uses an invalid IP address 0.0.0.x */
+ if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
+ debug2("channel %d: socks4a request", c->self);
+ /* ... and needs an extra string (the hostname) */
+ need = 2;
+ }
+ /* Check for terminating NUL on the string(s) */
+ for (found = 0, i = len; i < have; i++) {
+ if (p[i] == '\0') {
+ found++;
+ if (found == need)
+ break;
+ }
+ if (i > 1024) {
+ /* the peer is probably sending garbage */
+ debug("channel %d: decode socks4: too long",
+ c->self);
+ return -1;
+ }
+ }
+ if (found < need)
+ return 0;
+ buffer_get(&c->input, (char *)&s4_req.version, 1);
+ buffer_get(&c->input, (char *)&s4_req.command, 1);
+ buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
+ buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
+ have = buffer_len(&c->input);
+ p = buffer_ptr(&c->input);
+ len = strlen(p);
+ debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
+ len++; /* trailing '\0' */
+ if (len > have)
+ fatal("channel %d: decode socks4: len %d > have %d",
+ c->self, len, have);
+ strlcpy(username, p, sizeof(username));
+ buffer_consume(&c->input, len);
+
+ if (c->path != NULL) {
+ xfree(c->path);
+ c->path = NULL;
+ }
+ if (need == 1) { /* SOCKS4: one string */
+ host = inet_ntoa(s4_req.dest_addr);
+ c->path = xstrdup(host);
+ } else { /* SOCKS4A: two strings */
+ have = buffer_len(&c->input);
+ p = buffer_ptr(&c->input);
+ len = strlen(p);
+ debug2("channel %d: decode socks4a: host %s/%d",
+ c->self, p, len);
+ len++; /* trailing '\0' */
+ if (len > have)
+ fatal("channel %d: decode socks4a: len %d > have %d",
+ c->self, len, have);
+ if (len > NI_MAXHOST) {
+ error("channel %d: hostname \"%.100s\" too long",
+ c->self, p);
+ return -1;
+ }
+ c->path = xstrdup(p);
+ buffer_consume(&c->input, len);
+ }
+ c->host_port = ntohs(s4_req.dest_port);
+
+ debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
+ c->self, c->path, c->host_port, s4_req.command);
+
+ if (s4_req.command != 1) {
+ debug("channel %d: cannot handle: %s cn %d",
+ c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
+ return -1;
+ }
+ s4_rsp.version = 0; /* vn: 0 for reply */
+ s4_rsp.command = 90; /* cd: req granted */
+ s4_rsp.dest_port = 0; /* ignored */
+ s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
+ buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
+ return 1;
+}
+
+/* try to decode a socks5 header */
+#define SSH_SOCKS5_AUTHDONE 0x1000
+#define SSH_SOCKS5_NOAUTH 0x00
+#define SSH_SOCKS5_IPV4 0x01
+#define SSH_SOCKS5_DOMAIN 0x03
+#define SSH_SOCKS5_IPV6 0x04
+#define SSH_SOCKS5_CONNECT 0x01
+#define SSH_SOCKS5_SUCCESS 0x00
+
+/* ARGSUSED */
+static int
+channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
+{
+ struct {
+ u_int8_t version;
+ u_int8_t command;
+ u_int8_t reserved;
+ u_int8_t atyp;
+ } s5_req, s5_rsp;
+ u_int16_t dest_port;
+ u_char *p, dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
+ u_int have, need, i, found, nmethods, addrlen, af;
+
+ debug2("channel %d: decode socks5", c->self);
+ p = buffer_ptr(&c->input);
+ if (p[0] != 0x05)
+ return -1;
+ have = buffer_len(&c->input);
+ if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
+ /* format: ver | nmethods | methods */
+ if (have < 2)
+ return 0;
+ nmethods = p[1];
+ if (have < nmethods + 2)
+ return 0;
+ /* look for method: "NO AUTHENTICATION REQUIRED" */
+ for (found = 0, i = 2; i < nmethods + 2; i++) {
+ if (p[i] == SSH_SOCKS5_NOAUTH) {
+ found = 1;
+ break;
+ }
+ }
+ if (!found) {
+ debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
+ c->self);
+ return -1;
+ }
+ buffer_consume(&c->input, nmethods + 2);
+ buffer_put_char(&c->output, 0x05); /* version */
+ buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
+ FD_SET(c->sock, writeset);
+ c->flags |= SSH_SOCKS5_AUTHDONE;
+ debug2("channel %d: socks5 auth done", c->self);
+ return 0; /* need more */
+ }
+ debug2("channel %d: socks5 post auth", c->self);
+ if (have < sizeof(s5_req)+1)
+ return 0; /* need more */
+ memcpy(&s5_req, p, sizeof(s5_req));
+ if (s5_req.version != 0x05 ||
+ s5_req.command != SSH_SOCKS5_CONNECT ||
+ s5_req.reserved != 0x00) {
+ debug2("channel %d: only socks5 connect supported", c->self);
+ return -1;
+ }
+ switch (s5_req.atyp){
+ case SSH_SOCKS5_IPV4:
+ addrlen = 4;
+ af = AF_INET;
+ break;
+ case SSH_SOCKS5_DOMAIN:
+ addrlen = p[sizeof(s5_req)];
+ af = -1;
+ break;
+ case SSH_SOCKS5_IPV6:
+ addrlen = 16;
+ af = AF_INET6;
+ break;
+ default:
+ debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
+ return -1;
+ }
+ need = sizeof(s5_req) + addrlen + 2;
+ if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
+ need++;
+ if (have < need)
+ return 0;
+ buffer_consume(&c->input, sizeof(s5_req));
+ if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
+ buffer_consume(&c->input, 1); /* host string length */
+ buffer_get(&c->input, (char *)&dest_addr, addrlen);
+ buffer_get(&c->input, (char *)&dest_port, 2);
+ dest_addr[addrlen] = '\0';
+ if (c->path != NULL) {
+ xfree(c->path);
+ c->path = NULL;
+ }
+ if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
+ if (addrlen >= NI_MAXHOST) {
+ error("channel %d: dynamic request: socks5 hostname "
+ "\"%.100s\" too long", c->self, dest_addr);
+ return -1;
+ }
+ c->path = xstrdup(dest_addr);
+ } else {
+ if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
+ return -1;
+ c->path = xstrdup(ntop);
+ }
+ c->host_port = ntohs(dest_port);
+
+ debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
+ c->self, c->path, c->host_port, s5_req.command);
+
+ s5_rsp.version = 0x05;
+ s5_rsp.command = SSH_SOCKS5_SUCCESS;
+ s5_rsp.reserved = 0; /* ignored */
+ s5_rsp.atyp = SSH_SOCKS5_IPV4;
+ ((struct in_addr *)&dest_addr)->s_addr = INADDR_ANY;
+ dest_port = 0; /* ignored */
+
+ buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
+ buffer_append(&c->output, &dest_addr, sizeof(struct in_addr));
+ buffer_append(&c->output, &dest_port, sizeof(dest_port));
+ return 1;
+}
+
+Channel *
+channel_connect_stdio_fwd(const char *host_to_connect, u_short port_to_connect,
+ int in, int out)
+{
+ Channel *c;
+
+ debug("channel_connect_stdio_fwd %s:%d", host_to_connect,
+ port_to_connect);
+
+ c = channel_new("stdio-forward", SSH_CHANNEL_OPENING, in, out,
+ -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
+ 0, "stdio-forward", /*nonblock*/0);
+
+ c->path = xstrdup(host_to_connect);
+ c->host_port = port_to_connect;
+ c->listening_port = 0;
+ c->force_drain = 1;
+
+ channel_register_fds(c, in, out, -1, 0, 1, 0);
+ port_open_helper(c, "direct-tcpip");
+
+ return c;
+}
+
+/* dynamic port forwarding */
+static void
+channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
+{
+ u_char *p;
+ u_int have;
+ int ret;
+
+ have = buffer_len(&c->input);
+ debug2("channel %d: pre_dynamic: have %d", c->self, have);
+ /* buffer_dump(&c->input); */
+ /* check if the fixed size part of the packet is in buffer. */
+ if (have < 3) {
+ /* need more */
+ FD_SET(c->sock, readset);
+ return;
+ }
+ /* try to guess the protocol */
+ p = buffer_ptr(&c->input);
+ switch (p[0]) {
+ case 0x04:
+ ret = channel_decode_socks4(c, readset, writeset);
+ break;
+ case 0x05:
+ ret = channel_decode_socks5(c, readset, writeset);
+ break;
+ default:
+ ret = -1;
+ break;
+ }
+ if (ret < 0) {
+ chan_mark_dead(c);
+ } else if (ret == 0) {
+ debug2("channel %d: pre_dynamic: need more", c->self);
+ /* need more */
+ FD_SET(c->sock, readset);
+ } else {
+ /* switch to the next state */
+ c->type = SSH_CHANNEL_OPENING;
+ port_open_helper(c, "direct-tcpip");
}
}
/* This is our fake X11 server socket. */
-void
-channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
+/* ARGSUSED */
+static void
+channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
{
- struct sockaddr addr;
- int newsock, newch;
+ Channel *nc;
+ struct sockaddr_storage addr;
+ int newsock;
socklen_t addrlen;
- char buf[16384], *remote_hostname;
+ char buf[16384], *remote_ipaddr;
int remote_port;
if (FD_ISSET(c->sock, readset)) {
debug("X11 connection requested.");
addrlen = sizeof(addr);
- newsock = accept(c->sock, &addr, &addrlen);
+ newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
+ if (c->single_connection) {
+ debug2("single_connection: closing X11 listener.");
+ channel_close_fd(&c->sock);
+ chan_mark_dead(c);
+ }
if (newsock < 0) {
error("accept: %.100s", strerror(errno));
return;
}
- remote_hostname = get_remote_hostname(newsock);
+ set_nodelay(newsock);
+ remote_ipaddr = get_peer_ipaddr(newsock);
remote_port = get_peer_port(newsock);
snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
- remote_hostname, remote_port);
+ remote_ipaddr, remote_port);
- newch = channel_new("x11",
+ nc = channel_new("accepted x11 socket",
SSH_CHANNEL_OPENING, newsock, newsock, -1,
- c->local_window_max, c->local_maxpacket,
- 0, xstrdup(buf));
+ c->local_window_max, c->local_maxpacket, 0, buf, 1);
if (compat20) {
packet_start(SSH2_MSG_CHANNEL_OPEN);
packet_put_cstring("x11");
- packet_put_int(newch);
- packet_put_int(c->local_window_max);
- packet_put_int(c->local_maxpacket);
- /* originator host and port */
- packet_put_cstring(remote_hostname);
+ packet_put_int(nc->self);
+ packet_put_int(nc->local_window_max);
+ packet_put_int(nc->local_maxpacket);
+ /* originator ipaddr and port */
+ packet_put_cstring(remote_ipaddr);
if (datafellows & SSH_BUG_X11FWD) {
- debug("ssh2 x11 bug compat mode");
+ debug2("ssh2 x11 bug compat mode");
} else {
packet_put_int(remote_port);
}
packet_send();
} else {
packet_start(SSH_SMSG_X11_OPEN);
- packet_put_int(newch);
- if (have_hostname_in_open)
- packet_put_string(buf, strlen(buf));
+ packet_put_int(nc->self);
+ if (packet_get_protocol_flags() &
+ SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
+ packet_put_cstring(buf);
packet_send();
}
- xfree(remote_hostname);
+ xfree(remote_ipaddr);
+ }
+}
+
+static void
+port_open_helper(Channel *c, char *rtype)
+{
+ int direct;
+ char buf[1024];
+ char *remote_ipaddr = get_peer_ipaddr(c->sock);
+ int remote_port = get_peer_port(c->sock);
+
+ direct = (strcmp(rtype, "direct-tcpip") == 0);
+
+ snprintf(buf, sizeof buf,
+ "%s: listening port %d for %.100s port %d, "
+ "connect from %.200s port %d",
+ rtype, c->listening_port, c->path, c->host_port,
+ remote_ipaddr, remote_port);
+
+ xfree(c->remote_name);
+ c->remote_name = xstrdup(buf);
+
+ if (compat20) {
+ packet_start(SSH2_MSG_CHANNEL_OPEN);
+ packet_put_cstring(rtype);
+ packet_put_int(c->self);
+ packet_put_int(c->local_window_max);
+ packet_put_int(c->local_maxpacket);
+ if (direct) {
+ /* target host, port */
+ packet_put_cstring(c->path);
+ packet_put_int(c->host_port);
+ } else {
+ /* listen address, port */
+ packet_put_cstring(c->path);
+ packet_put_int(c->listening_port);
+ }
+ /* originator host and port */
+ packet_put_cstring(remote_ipaddr);
+ packet_put_int((u_int)remote_port);
+ packet_send();
+ } else {
+ packet_start(SSH_MSG_PORT_OPEN);
+ packet_put_int(c->self);
+ packet_put_cstring(c->path);
+ packet_put_int(c->host_port);
+ if (packet_get_protocol_flags() &
+ SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
+ packet_put_cstring(c->remote_name);
+ packet_send();
}
+ xfree(remote_ipaddr);
+}
+
+static void
+channel_set_reuseaddr(int fd)
+{
+ int on = 1;
+
+ /*
+ * Set socket options.
+ * Allow local port reuse in TIME_WAIT.
+ */
+ if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
+ error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
}
/*
* This socket is listening for connections to a forwarded TCP/IP port.
*/
-void
-channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
+/* ARGSUSED */
+static void
+channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
{
- struct sockaddr addr;
- int newsock, newch;
+ Channel *nc;
+ struct sockaddr_storage addr;
+ int newsock, nextstate;
socklen_t addrlen;
- char buf[1024], *remote_hostname;
- int remote_port;
+ char *rtype;
if (FD_ISSET(c->sock, readset)) {
debug("Connection to port %d forwarding "
"to %.100s port %d requested.",
c->listening_port, c->path, c->host_port);
+
+ if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
+ nextstate = SSH_CHANNEL_OPENING;
+ rtype = "forwarded-tcpip";
+ } else {
+ if (c->host_port == 0) {
+ nextstate = SSH_CHANNEL_DYNAMIC;
+ rtype = "dynamic-tcpip";
+ } else {
+ nextstate = SSH_CHANNEL_OPENING;
+ rtype = "direct-tcpip";
+ }
+ }
+
addrlen = sizeof(addr);
- newsock = accept(c->sock, &addr, &addrlen);
+ newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
if (newsock < 0) {
error("accept: %.100s", strerror(errno));
return;
}
- remote_hostname = get_remote_hostname(newsock);
- remote_port = get_peer_port(newsock);
- snprintf(buf, sizeof buf,
- "listen port %d for %.100s port %d, "
- "connect from %.200s port %d",
- c->listening_port, c->path, c->host_port,
- remote_hostname, remote_port);
- newch = channel_new("direct-tcpip",
- SSH_CHANNEL_OPENING, newsock, newsock, -1,
- c->local_window_max, c->local_maxpacket,
- 0, xstrdup(buf));
- if (compat20) {
- packet_start(SSH2_MSG_CHANNEL_OPEN);
- packet_put_cstring("direct-tcpip");
- packet_put_int(newch);
- packet_put_int(c->local_window_max);
- packet_put_int(c->local_maxpacket);
- /* target host and port */
- packet_put_string(c->path, strlen(c->path));
- packet_put_int(c->host_port);
- /* originator host and port */
- packet_put_cstring(remote_hostname);
- packet_put_int(remote_port);
- packet_send();
- } else {
- packet_start(SSH_MSG_PORT_OPEN);
- packet_put_int(newch);
- packet_put_string(c->path, strlen(c->path));
- packet_put_int(c->host_port);
- if (have_hostname_in_open) {
- packet_put_string(buf, strlen(buf));
- }
- packet_send();
- }
- xfree(remote_hostname);
+ set_nodelay(newsock);
+ nc = channel_new(rtype, nextstate, newsock, newsock, -1,
+ c->local_window_max, c->local_maxpacket, 0, rtype, 1);
+ nc->listening_port = c->listening_port;
+ nc->host_port = c->host_port;
+ if (c->path != NULL)
+ nc->path = xstrdup(c->path);
+
+ if (nextstate != SSH_CHANNEL_DYNAMIC)
+ port_open_helper(nc, rtype);
}
}
* This is the authentication agent socket listening for connections from
* clients.
*/
-void
-channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
+/* ARGSUSED */
+static void
+channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
{
- struct sockaddr addr;
- int newsock, newch;
+ Channel *nc;
+ int newsock;
+ struct sockaddr_storage addr;
socklen_t addrlen;
if (FD_ISSET(c->sock, readset)) {
addrlen = sizeof(addr);
- newsock = accept(c->sock, &addr, &addrlen);
+ newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
if (newsock < 0) {
error("accept from auth socket: %.100s", strerror(errno));
return;
}
- newch = channel_allocate(SSH_CHANNEL_OPENING, newsock,
- xstrdup("accepted auth socket"));
- packet_start(SSH_SMSG_AGENT_OPEN);
- packet_put_int(newch);
+ nc = channel_new("accepted auth socket",
+ SSH_CHANNEL_OPENING, newsock, newsock, -1,
+ c->local_window_max, c->local_maxpacket,
+ 0, "accepted auth socket", 1);
+ if (compat20) {
+ packet_start(SSH2_MSG_CHANNEL_OPEN);
+ packet_put_cstring("auth-agent@openssh.com");
+ packet_put_int(nc->self);
+ packet_put_int(c->local_window_max);
+ packet_put_int(c->local_maxpacket);
+ } else {
+ packet_start(SSH_SMSG_AGENT_OPEN);
+ packet_put_int(nc->self);
+ }
+ packet_send();
+ }
+}
+
+/* ARGSUSED */
+static void
+channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
+{
+ int err = 0, sock;
+ socklen_t sz = sizeof(err);
+
+ if (FD_ISSET(c->sock, writeset)) {
+ if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
+ err = errno;
+ error("getsockopt SO_ERROR failed");
+ }
+ if (err == 0) {
+ debug("channel %d: connected to %s port %d",
+ c->self, c->connect_ctx.host, c->connect_ctx.port);
+ channel_connect_ctx_free(&c->connect_ctx);
+ c->type = SSH_CHANNEL_OPEN;
+ if (compat20) {
+ packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
+ packet_put_int(c->remote_id);
+ packet_put_int(c->self);
+ packet_put_int(c->local_window);
+ packet_put_int(c->local_maxpacket);
+ } else {
+ packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
+ packet_put_int(c->remote_id);
+ packet_put_int(c->self);
+ }
+ } else {
+ debug("channel %d: connection failed: %s",
+ c->self, strerror(err));
+ /* Try next address, if any */
+ if ((sock = connect_next(&c->connect_ctx)) > 0) {
+ close(c->sock);
+ c->sock = c->rfd = c->wfd = sock;
+ channel_max_fd = channel_find_maxfd();
+ return;
+ }
+ /* Exhausted all addresses */
+ error("connect_to %.100s port %d: failed.",
+ c->connect_ctx.host, c->connect_ctx.port);
+ channel_connect_ctx_free(&c->connect_ctx);
+ if (compat20) {
+ packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
+ packet_put_int(c->remote_id);
+ packet_put_int(SSH2_OPEN_CONNECT_FAILED);
+ if (!(datafellows & SSH_BUG_OPENFAILURE)) {
+ packet_put_cstring(strerror(err));
+ packet_put_cstring("");
+ }
+ } else {
+ packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
+ packet_put_int(c->remote_id);
+ }
+ chan_mark_dead(c);
+ }
packet_send();
}
}
-int
-channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
+/* ARGSUSED */
+static int
+channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
{
- char buf[16*1024];
- int len;
+ char buf[CHAN_RBUF];
+ int len, force;
- if (c->rfd != -1 &&
- FD_ISSET(c->rfd, readset)) {
+ force = c->isatty && c->detach_close && c->istate != CHAN_INPUT_CLOSED;
+ if (c->rfd != -1 && (force || FD_ISSET(c->rfd, readset))) {
+ errno = 0;
len = read(c->rfd, buf, sizeof(buf));
- if (len < 0 && (errno == EINTR || errno == EAGAIN))
+ if (len < 0 && (errno == EINTR ||
+ ((errno == EAGAIN || errno == EWOULDBLOCK) && !force)))
return 1;
+#ifndef PTY_ZEROREAD
if (len <= 0) {
- debug("channel %d: read<=0 rfd %d len %d",
+#else
+ if ((!c->isatty && len <= 0) ||
+ (c->isatty && (len < 0 || (len == 0 && errno != 0)))) {
+#endif
+ debug2("channel %d: read<=0 rfd %d len %d",
c->self, c->rfd, len);
- if (compat13) {
- buffer_consume(&c->output, buffer_len(&c->output));
+ if (c->type != SSH_CHANNEL_OPEN) {
+ debug2("channel %d: not open", c->self);
+ chan_mark_dead(c);
+ return -1;
+ } else if (compat13) {
+ buffer_clear(&c->output);
c->type = SSH_CHANNEL_INPUT_DRAINING;
- debug("Channel %d status set to input draining.", c->self);
+ debug2("channel %d: input draining.", c->self);
} else {
chan_read_failed(c);
}
return -1;
}
- buffer_append(&c->input, buf, len);
+ if (c->input_filter != NULL) {
+ if (c->input_filter(c, buf, len) == -1) {
+ debug2("channel %d: filter stops", c->self);
+ chan_read_failed(c);
+ }
+ } else if (c->datagram) {
+ buffer_put_string(&c->input, buf, len);
+ } else {
+ buffer_append(&c->input, buf, len);
+ }
}
return 1;
}
-int
-channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
+
+/* ARGSUSED */
+static int
+channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
{
+ struct termios tio;
+ u_char *data = NULL, *buf;
+ u_int dlen;
int len;
/* Send buffered output data to the socket. */
if (c->wfd != -1 &&
FD_ISSET(c->wfd, writeset) &&
buffer_len(&c->output) > 0) {
- len = write(c->wfd, buffer_ptr(&c->output),
- buffer_len(&c->output));
- if (len < 0 && (errno == EINTR || errno == EAGAIN))
+ if (c->output_filter != NULL) {
+ if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
+ debug2("channel %d: filter stops", c->self);
+ if (c->type != SSH_CHANNEL_OPEN)
+ chan_mark_dead(c);
+ else
+ chan_write_failed(c);
+ return -1;
+ }
+ } else if (c->datagram) {
+ buf = data = buffer_get_string(&c->output, &dlen);
+ } else {
+ buf = data = buffer_ptr(&c->output);
+ dlen = buffer_len(&c->output);
+ }
+
+ if (c->datagram) {
+ /* ignore truncated writes, datagrams might get lost */
+ c->local_consumed += dlen + 4;
+ len = write(c->wfd, buf, dlen);
+ xfree(data);
+ if (len < 0 && (errno == EINTR || errno == EAGAIN ||
+ errno == EWOULDBLOCK))
+ return 1;
+ if (len <= 0) {
+ if (c->type != SSH_CHANNEL_OPEN)
+ chan_mark_dead(c);
+ else
+ chan_write_failed(c);
+ return -1;
+ }
+ return 1;
+ }
+#ifdef _AIX
+ /* XXX: Later AIX versions can't push as much data to tty */
+ if (compat20 && c->wfd_isatty)
+ dlen = MIN(dlen, 8*1024);
+#endif
+
+ len = write(c->wfd, buf, dlen);
+ if (len < 0 &&
+ (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK))
return 1;
if (len <= 0) {
- if (compat13) {
- buffer_consume(&c->output, buffer_len(&c->output));
- debug("Channel %d status set to input draining.", c->self);
+ if (c->type != SSH_CHANNEL_OPEN) {
+ debug2("channel %d: not open", c->self);
+ chan_mark_dead(c);
+ return -1;
+ } else if (compat13) {
+ buffer_clear(&c->output);
+ debug2("channel %d: input draining.", c->self);
c->type = SSH_CHANNEL_INPUT_DRAINING;
} else {
chan_write_failed(c);
}
return -1;
}
+#ifndef BROKEN_TCGETATTR_ICANON
+ if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') {
+ if (tcgetattr(c->wfd, &tio) == 0 &&
+ !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
+ /*
+ * Simulate echo to reduce the impact of
+ * traffic analysis. We need to match the
+ * size of a SSH2_MSG_CHANNEL_DATA message
+ * (4 byte channel id + buf)
+ */
+ packet_send_ignore(4 + len);
+ packet_send();
+ }
+ }
+#endif
buffer_consume(&c->output, len);
if (compat20 && len > 0) {
c->local_consumed += len;
}
return 1;
}
-int
-channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
+
+static int
+channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
{
- char buf[16*1024];
+ char buf[CHAN_RBUF];
int len;
/** XXX handle drain efd, too */
buffer_len(&c->extended) > 0) {
len = write(c->efd, buffer_ptr(&c->extended),
buffer_len(&c->extended));
- debug("channel %d: written %d to efd %d",
+ debug2("channel %d: written %d to efd %d",
c->self, len, c->efd);
- if (len > 0) {
+ if (len < 0 && (errno == EINTR || errno == EAGAIN ||
+ errno == EWOULDBLOCK))
+ return 1;
+ if (len <= 0) {
+ debug2("channel %d: closing write-efd %d",
+ c->self, c->efd);
+ channel_close_fd(&c->efd);
+ } else {
buffer_consume(&c->extended, len);
c->local_consumed += len;
}
} else if (c->extended_usage == CHAN_EXTENDED_READ &&
- FD_ISSET(c->efd, readset)) {
+ (c->detach_close || FD_ISSET(c->efd, readset))) {
len = read(c->efd, buf, sizeof(buf));
- debug("channel %d: read %d from efd %d",
- c->self, len, c->efd);
- if (len == 0) {
- debug("channel %d: closing efd %d",
+ debug2("channel %d: read %d from efd %d",
+ c->self, len, c->efd);
+ if (len < 0 && (errno == EINTR || ((errno == EAGAIN ||
+ errno == EWOULDBLOCK) && !c->detach_close)))
+ return 1;
+ if (len <= 0) {
+ debug2("channel %d: closing read-efd %d",
c->self, c->efd);
- close(c->efd);
- c->efd = -1;
- } else if (len > 0)
+ channel_close_fd(&c->efd);
+ } else {
buffer_append(&c->extended, buf, len);
+ }
}
}
return 1;
}
-int
-channel_check_window(Channel *c, fd_set * readset, fd_set * writeset)
+
+static int
+channel_check_window(Channel *c)
{
- if (!(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
- c->local_window < c->local_window_max/2 &&
+ if (c->type == SSH_CHANNEL_OPEN &&
+ !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
+ ((c->local_window_max - c->local_window >
+ c->local_maxpacket*3) ||
+ c->local_window < c->local_window_max/2) &&
c->local_consumed > 0) {
packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
packet_put_int(c->remote_id);
packet_put_int(c->local_consumed);
packet_send();
- debug("channel %d: window %d sent adjust %d",
+ debug2("channel %d: window %d sent adjust %d",
c->self, c->local_window,
c->local_consumed);
c->local_window += c->local_consumed;
return 1;
}
-void
-channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset)
+static void
+channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
{
channel_handle_rfd(c, readset, writeset);
channel_handle_wfd(c, readset, writeset);
+ if (!compat20)
+ return;
+ channel_handle_efd(c, readset, writeset);
+ channel_check_window(c);
}
-void
-channel_post_open_2(Channel *c, fd_set * readset, fd_set * writeset)
+static u_int
+read_mux(Channel *c, u_int need)
{
- channel_handle_rfd(c, readset, writeset);
- channel_handle_wfd(c, readset, writeset);
- channel_handle_efd(c, readset, writeset);
- channel_check_window(c, readset, writeset);
+ char buf[CHAN_RBUF];
+ int len;
+ u_int rlen;
+
+ if (buffer_len(&c->input) < need) {
+ rlen = need - buffer_len(&c->input);
+ len = read(c->rfd, buf, MIN(rlen, CHAN_RBUF));
+ if (len <= 0) {
+ if (errno != EINTR && errno != EAGAIN) {
+ debug2("channel %d: ctl read<=0 rfd %d len %d",
+ c->self, c->rfd, len);
+ chan_read_failed(c);
+ return 0;
+ }
+ } else
+ buffer_append(&c->input, buf, len);
+ }
+ return buffer_len(&c->input);
}
-void
-channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset)
+static void
+channel_post_mux_client(Channel *c, fd_set *readset, fd_set *writeset)
+{
+ u_int need;
+ ssize_t len;
+
+ if (!compat20)
+ fatal("%s: entered with !compat20", __func__);
+
+ if (c->rfd != -1 && FD_ISSET(c->rfd, readset) &&
+ (c->istate == CHAN_INPUT_OPEN ||
+ c->istate == CHAN_INPUT_WAIT_DRAIN)) {
+ /*
+ * Don't not read past the precise end of packets to
+ * avoid disrupting fd passing.
+ */
+ if (read_mux(c, 4) < 4) /* read header */
+ return;
+ need = get_u32(buffer_ptr(&c->input));
+#define CHANNEL_MUX_MAX_PACKET (256 * 1024)
+ if (need > CHANNEL_MUX_MAX_PACKET) {
+ debug2("channel %d: packet too big %u > %u",
+ c->self, CHANNEL_MUX_MAX_PACKET, need);
+ chan_rcvd_oclose(c);
+ return;
+ }
+ if (read_mux(c, need + 4) < need + 4) /* read body */
+ return;
+ if (c->mux_rcb(c) != 0) {
+ debug("channel %d: mux_rcb failed", c->self);
+ chan_mark_dead(c);
+ return;
+ }
+ }
+
+ if (c->wfd != -1 && FD_ISSET(c->wfd, writeset) &&
+ buffer_len(&c->output) > 0) {
+ len = write(c->wfd, buffer_ptr(&c->output),
+ buffer_len(&c->output));
+ if (len < 0 && (errno == EINTR || errno == EAGAIN))
+ return;
+ if (len <= 0) {
+ chan_mark_dead(c);
+ return;
+ }
+ buffer_consume(&c->output, len);
+ }
+}
+
+static void
+channel_post_mux_listener(Channel *c, fd_set *readset, fd_set *writeset)
+{
+ Channel *nc;
+ struct sockaddr_storage addr;
+ socklen_t addrlen;
+ int newsock;
+ uid_t euid;
+ gid_t egid;
+
+ if (!FD_ISSET(c->sock, readset))
+ return;
+
+ debug("multiplexing control connection");
+
+ /*
+ * Accept connection on control socket
+ */
+ memset(&addr, 0, sizeof(addr));
+ addrlen = sizeof(addr);
+ if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
+ &addrlen)) == -1) {
+ error("%s accept: %s", __func__, strerror(errno));
+ return;
+ }
+
+ if (getpeereid(newsock, &euid, &egid) < 0) {
+ error("%s getpeereid failed: %s", __func__,
+ strerror(errno));
+ close(newsock);
+ return;
+ }
+ if ((euid != 0) && (getuid() != euid)) {
+ error("multiplex uid mismatch: peer euid %u != uid %u",
+ (u_int)euid, (u_int)getuid());
+ close(newsock);
+ return;
+ }
+ nc = channel_new("multiplex client", SSH_CHANNEL_MUX_CLIENT,
+ newsock, newsock, -1, c->local_window_max,
+ c->local_maxpacket, 0, "mux-control", 1);
+ nc->mux_rcb = c->mux_rcb;
+ debug3("%s: new mux channel %d fd %d", __func__,
+ nc->self, nc->sock);
+ /* establish state */
+ nc->mux_rcb(nc);
+ /* mux state transitions must not elicit protocol messages */
+ nc->flags |= CHAN_LOCAL;
+}
+
+/* ARGSUSED */
+static void
+channel_post_output_drain_13(Channel *c, fd_set *readset, fd_set *writeset)
{
int len;
+
/* Send buffered output data to the socket. */
if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
len = write(c->sock, buffer_ptr(&c->output),
buffer_len(&c->output));
if (len <= 0)
- buffer_consume(&c->output, buffer_len(&c->output));
+ buffer_clear(&c->output);
else
buffer_consume(&c->output, len);
}
}
-void
+static void
channel_handler_init_20(void)
{
- channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20;
+ channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
+ channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
+ channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
+ channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
+ channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
+ channel_pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
+ channel_pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
- channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2;
+ channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
+ channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
+ channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
+ channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
+ channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
+ channel_post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
+ channel_post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
}
-void
+static void
channel_handler_init_13(void)
{
channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
+ channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
+ channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
- channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
+ channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
+ channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
+ channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
}
-void
+static void
channel_handler_init_15(void)
{
- channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15;
+ channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
+ channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
+ channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
- channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
+ channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
+ channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
+ channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
}
-void
+static void
channel_handler_init(void)
{
int i;
- for(i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
+
+ for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
channel_pre[i] = NULL;
channel_post[i] = NULL;
}
channel_handler_init_15();
}
-void
-channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset)
+/* gc dead channels */
+static void
+channel_garbage_collect(Channel *c)
+{
+ if (c == NULL)
+ return;
+ if (c->detach_user != NULL) {
+ if (!chan_is_dead(c, c->detach_close))
+ return;
+ debug2("channel %d: gc: notify user", c->self);
+ c->detach_user(c->self, NULL);
+ /* if we still have a callback */
+ if (c->detach_user != NULL)
+ return;
+ debug2("channel %d: gc: user detached", c->self);
+ }
+ if (!chan_is_dead(c, 1))
+ return;
+ debug2("channel %d: garbage collecting", c->self);
+ channel_free(c);
+}
+
+static void
+channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset)
{
static int did_init = 0;
- int i;
+ u_int i, oalloc;
Channel *c;
if (!did_init) {
channel_handler_init();
did_init = 1;
}
- for (i = 0; i < channels_alloc; i++) {
- c = &channels[i];
- if (c->type == SSH_CHANNEL_FREE)
+ for (i = 0, oalloc = channels_alloc; i < oalloc; i++) {
+ c = channels[i];
+ if (c == NULL)
continue;
- if (ftab[c->type] == NULL)
- continue;
- (*ftab[c->type])(c, readset, writeset);
- chan_delete_if_full_closed(c);
+ if (c->delayed) {
+ if (ftab == channel_pre)
+ c->delayed = 0;
+ else
+ continue;
+ }
+ if (ftab[c->type] != NULL)
+ (*ftab[c->type])(c, readset, writeset);
+ channel_garbage_collect(c);
}
}
+/*
+ * Allocate/update select bitmasks and add any bits relevant to channels in
+ * select bitmasks.
+ */
void
-channel_prepare_select(fd_set * readset, fd_set * writeset)
+channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
+ u_int *nallocp, int rekeying)
{
- channel_handler(channel_pre, readset, writeset);
+ u_int n, sz, nfdset;
+
+ n = MAX(*maxfdp, channel_max_fd);
+
+ nfdset = howmany(n+1, NFDBITS);
+ /* Explicitly test here, because xrealloc isn't always called */
+ if (nfdset && SIZE_T_MAX / nfdset < sizeof(fd_mask))
+ fatal("channel_prepare_select: max_fd (%d) is too large", n);
+ sz = nfdset * sizeof(fd_mask);
+
+ /* perhaps check sz < nalloc/2 and shrink? */
+ if (*readsetp == NULL || sz > *nallocp) {
+ *readsetp = xrealloc(*readsetp, nfdset, sizeof(fd_mask));
+ *writesetp = xrealloc(*writesetp, nfdset, sizeof(fd_mask));
+ *nallocp = sz;
+ }
+ *maxfdp = n;
+ memset(*readsetp, 0, sz);
+ memset(*writesetp, 0, sz);
+
+ if (!rekeying)
+ channel_handler(channel_pre, *readsetp, *writesetp);
}
+/*
+ * After select, perform any appropriate operations for channels which have
+ * events pending.
+ */
void
-channel_after_select(fd_set * readset, fd_set * writeset)
+channel_after_select(fd_set *readset, fd_set *writeset)
{
channel_handler(channel_post, readset, writeset);
}
-/* If there is data to send to the connection, send some of it now. */
+/* If there is data to send to the connection, enqueue some of it now. */
void
-channel_output_poll()
+channel_output_poll(void)
{
- int len, i;
Channel *c;
+ u_int i, len;
for (i = 0; i < channels_alloc; i++) {
- c = &channels[i];
+ c = channels[i];
+ if (c == NULL)
+ continue;
- /* We are only interested in channels that can have buffered incoming data. */
+ /*
+ * We are only interested in channels that can have buffered
+ * incoming data.
+ */
if (compat13) {
if (c->type != SSH_CHANNEL_OPEN &&
c->type != SSH_CHANNEL_INPUT_DRAINING)
} else {
if (c->type != SSH_CHANNEL_OPEN)
continue;
- if (c->istate != CHAN_INPUT_OPEN &&
- c->istate != CHAN_INPUT_WAIT_DRAIN)
- continue;
}
if (compat20 &&
(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
- debug("channel: %d: no data after CLOSE", c->self);
+ /* XXX is this true? */
+ debug3("channel %d: will not send data after close", c->self);
continue;
}
/* Get the amount of buffered data for this channel. */
- len = buffer_len(&c->input);
- if (len > 0) {
- /* Send some data for the other side over the secure connection. */
+ if ((c->istate == CHAN_INPUT_OPEN ||
+ c->istate == CHAN_INPUT_WAIT_DRAIN) &&
+ (len = buffer_len(&c->input)) > 0) {
+ if (c->datagram) {
+ if (len > 0) {
+ u_char *data;
+ u_int dlen;
+
+ data = buffer_get_string(&c->input,
+ &dlen);
+ packet_start(SSH2_MSG_CHANNEL_DATA);
+ packet_put_int(c->remote_id);
+ packet_put_string(data, dlen);
+ packet_send();
+ c->remote_window -= dlen + 4;
+ xfree(data);
+ }
+ continue;
+ }
+ /*
+ * Send some data for the other side over the secure
+ * connection.
+ */
if (compat20) {
if (len > c->remote_window)
len = c->remote_window;
fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
/*
* input-buffer is empty and read-socket shutdown:
- * tell peer, that we will not send more data: send IEOF
+ * tell peer, that we will not send more data: send IEOF.
+ * hack for extended data: delay EOF if EFD still in use.
*/
- chan_ibuf_empty(c);
+ if (CHANNEL_EFD_INPUT_ACTIVE(c))
+ debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
+ c->self, c->efd, buffer_len(&c->extended));
+ else
+ chan_ibuf_empty(c);
}
/* Send extended data, i.e. stderr */
if (compat20 &&
+ !(c->flags & CHAN_EOF_SENT) &&
c->remote_window > 0 &&
(len = buffer_len(&c->extended)) > 0 &&
c->extended_usage == CHAN_EXTENDED_READ) {
+ debug2("channel %d: rwin %u elen %u euse %d",
+ c->self, c->remote_window, buffer_len(&c->extended),
+ c->extended_usage);
if (len > c->remote_window)
len = c->remote_window;
if (len > c->remote_maxpacket)
packet_send();
buffer_consume(&c->extended, len);
c->remote_window -= len;
+ debug2("channel %d: sent ext data %d", c->self, len);
}
}
}
-/*
- * This is called when a packet of type CHANNEL_DATA has just been received.
- * The message type has already been consumed, but channel number and data is
- * still there.
- */
+/* -- protocol input */
+
+/* ARGSUSED */
void
-channel_input_data(int type, int plen)
+channel_input_data(int type, u_int32_t seq, void *ctxt)
{
int id;
char *data;
- unsigned int data_len;
+ u_int data_len;
Channel *c;
/* Get the channel number and verify it. */
c->type != SSH_CHANNEL_X11_OPEN)
return;
- /* same for protocol 1.5 if output end is no longer open */
- if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN)
- return;
-
/* Get the data. */
- data = packet_get_string(&data_len);
- packet_done();
+ data = packet_get_string_ptr(&data_len);
- if (compat20){
+ /*
+ * Ignore data for protocol > 1.3 if output end is no longer open.
+ * For protocol 2 the sending side is reducing its window as it sends
+ * data, so we must 'fake' consumption of the data in order to ensure
+ * that window updates are sent back. Otherwise the connection might
+ * deadlock.
+ */
+ if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) {
+ if (compat20) {
+ c->local_window -= data_len;
+ c->local_consumed += data_len;
+ }
+ return;
+ }
+
+ if (compat20) {
if (data_len > c->local_maxpacket) {
- log("channel %d: rcvd big packet %d, maxpack %d",
+ logit("channel %d: rcvd big packet %d, maxpack %d",
c->self, data_len, c->local_maxpacket);
}
if (data_len > c->local_window) {
- log("channel %d: rcvd too much data %d, win %d",
+ logit("channel %d: rcvd too much data %d, win %d",
c->self, data_len, c->local_window);
- xfree(data);
return;
}
c->local_window -= data_len;
- }else{
- packet_integrity_check(plen, 4 + 4 + data_len, type);
}
- buffer_append(&c->output, data, data_len);
- xfree(data);
+ if (c->datagram)
+ buffer_put_string(&c->output, data, data_len);
+ else
+ buffer_append(&c->output, data, data_len);
+ packet_check_eom();
}
+
+/* ARGSUSED */
void
-channel_input_extended_data(int type, int plen)
+channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
{
int id;
- int tcode;
char *data;
- unsigned int data_len;
+ u_int data_len, tcode;
Channel *c;
/* Get the channel number and verify it. */
if (c == NULL)
packet_disconnect("Received extended_data for bad channel %d.", id);
if (c->type != SSH_CHANNEL_OPEN) {
- log("channel %d: ext data for non open", id);
+ logit("channel %d: ext data for non open", id);
return;
}
+ if (c->flags & CHAN_EOF_RCVD) {
+ if (datafellows & SSH_BUG_EXTEOF)
+ debug("channel %d: accepting ext data after eof", id);
+ else
+ packet_disconnect("Received extended_data after EOF "
+ "on channel %d.", id);
+ }
tcode = packet_get_int();
if (c->efd == -1 ||
c->extended_usage != CHAN_EXTENDED_WRITE ||
tcode != SSH2_EXTENDED_DATA_STDERR) {
- log("channel %d: bad ext data", c->self);
+ logit("channel %d: bad ext data", c->self);
return;
}
data = packet_get_string(&data_len);
- packet_done();
+ packet_check_eom();
if (data_len > c->local_window) {
- log("channel %d: rcvd too much extended_data %d, win %d",
+ logit("channel %d: rcvd too much extended_data %d, win %d",
c->self, data_len, c->local_window);
xfree(data);
return;
}
- debug("channel %d: rcvd ext data %d", c->self, data_len);
+ debug2("channel %d: rcvd ext data %d", c->self, data_len);
c->local_window -= data_len;
buffer_append(&c->extended, data, data_len);
xfree(data);
}
-
-/*
- * Returns true if no channel has too much buffered data, and false if one or
- * more channel is overfull.
- */
-
-int
-channel_not_very_much_buffered_data()
-{
- unsigned int i;
- Channel *c;
-
- for (i = 0; i < channels_alloc; i++) {
- c = &channels[i];
- if (c->type == SSH_CHANNEL_OPEN) {
- if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) {
- debug("channel %d: big input buffer %d",
- c->self, buffer_len(&c->input));
- return 0;
- }
- if (buffer_len(&c->output) > packet_get_maxsize()) {
- debug("channel %d: big output buffer %d",
- c->self, buffer_len(&c->output));
- return 0;
- }
- }
- }
- return 1;
-}
-
+/* ARGSUSED */
void
-channel_input_ieof(int type, int plen)
+channel_input_ieof(int type, u_int32_t seq, void *ctxt)
{
int id;
Channel *c;
- packet_integrity_check(plen, 4, type);
-
id = packet_get_int();
+ packet_check_eom();
c = channel_lookup(id);
if (c == NULL)
packet_disconnect("Received ieof for nonexistent channel %d.", id);
chan_rcvd_ieof(c);
+
+ /* XXX force input close */
+ if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
+ debug("channel %d: FORCE input drain", c->self);
+ c->istate = CHAN_INPUT_WAIT_DRAIN;
+ if (buffer_len(&c->input) == 0)
+ chan_ibuf_empty(c);
+ }
+
}
+/* ARGSUSED */
void
-channel_input_close(int type, int plen)
+channel_input_close(int type, u_int32_t seq, void *ctxt)
{
int id;
Channel *c;
- packet_integrity_check(plen, 4, type);
-
id = packet_get_int();
+ packet_check_eom();
c = channel_lookup(id);
if (c == NULL)
packet_disconnect("Received close for nonexistent channel %d.", id);
* Not a closed channel - mark it as draining, which will
* cause it to be freed later.
*/
- buffer_consume(&c->input, buffer_len(&c->input));
+ buffer_clear(&c->input);
c->type = SSH_CHANNEL_OUTPUT_DRAINING;
}
}
/* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
+/* ARGSUSED */
void
-channel_input_oclose(int type, int plen)
+channel_input_oclose(int type, u_int32_t seq, void *ctxt)
{
int id = packet_get_int();
Channel *c = channel_lookup(id);
- packet_integrity_check(plen, 4, type);
+
+ packet_check_eom();
if (c == NULL)
packet_disconnect("Received oclose for nonexistent channel %d.", id);
chan_rcvd_oclose(c);
}
+/* ARGSUSED */
void
-channel_input_close_confirmation(int type, int plen)
+channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
{
int id = packet_get_int();
Channel *c = channel_lookup(id);
- packet_done();
+ packet_check_eom();
if (c == NULL)
packet_disconnect("Received close confirmation for "
"out-of-range channel %d.", id);
if (c->type != SSH_CHANNEL_CLOSED)
packet_disconnect("Received close confirmation for "
"non-closed channel %d (type %d).", id, c->type);
- channel_free(c->self);
+ channel_free(c);
}
+/* ARGSUSED */
void
-channel_input_open_confirmation(int type, int plen)
+channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
{
int id, remote_id;
Channel *c;
- if (!compat20)
- packet_integrity_check(plen, 4 + 4, type);
-
id = packet_get_int();
c = channel_lookup(id);
if (compat20) {
c->remote_window = packet_get_int();
c->remote_maxpacket = packet_get_int();
- packet_done();
- if (c->cb_fn != NULL && c->cb_event == type) {
- debug("callback start");
- c->cb_fn(c->self, c->cb_arg);
- debug("callback done");
+ if (c->open_confirm) {
+ debug2("callback start");
+ c->open_confirm(c->self, c->open_confirm_ctx);
+ debug2("callback done");
}
- debug("channel %d: open confirm rwindow %d rmax %d", c->self,
+ debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
c->remote_window, c->remote_maxpacket);
}
+ packet_check_eom();
}
-void
-channel_input_open_failure(int type, int plen)
+static char *
+reason2txt(int reason)
{
- int id;
- Channel *c;
-
- if (!compat20)
- packet_integrity_check(plen, 4, type);
-
- id = packet_get_int();
- c = channel_lookup(id);
-
- if (c==NULL || c->type != SSH_CHANNEL_OPENING)
- packet_disconnect("Received open failure for "
- "non-opening channel %d.", id);
- if (compat20) {
- int reason = packet_get_int();
- char *msg = packet_get_string(NULL);
- char *lang = packet_get_string(NULL);
- log("channel_open_failure: %d: reason %d: %s", id, reason, msg);
- packet_done();
- xfree(msg);
- xfree(lang);
+ switch (reason) {
+ case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
+ return "administratively prohibited";
+ case SSH2_OPEN_CONNECT_FAILED:
+ return "connect failed";
+ case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
+ return "unknown channel type";
+ case SSH2_OPEN_RESOURCE_SHORTAGE:
+ return "resource shortage";
}
- /* Free the channel. This will also close the socket. */
- channel_free(id);
+ return "unknown reason";
}
+/* ARGSUSED */
void
-channel_input_channel_request(int type, int plen)
+channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
{
- int id;
+ int id, reason;
+ char *msg = NULL, *lang = NULL;
Channel *c;
id = packet_get_int();
c = channel_lookup(id);
- if (c == NULL ||
- (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL))
- packet_disconnect("Received request for "
- "non-open channel %d.", id);
- if (c->cb_fn != NULL && c->cb_event == type) {
- debug("callback start");
- c->cb_fn(c->self, c->cb_arg);
- debug("callback done");
- } else {
- char *service = packet_get_string(NULL);
- debug("channel: %d rcvd request for %s", c->self, service);
-debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event);
- xfree(service);
+ if (c==NULL || c->type != SSH_CHANNEL_OPENING)
+ packet_disconnect("Received open failure for "
+ "non-opening channel %d.", id);
+ if (compat20) {
+ reason = packet_get_int();
+ if (!(datafellows & SSH_BUG_OPENFAILURE)) {
+ msg = packet_get_string(NULL);
+ lang = packet_get_string(NULL);
+ }
+ logit("channel %d: open failed: %s%s%s", id,
+ reason2txt(reason), msg ? ": ": "", msg ? msg : "");
+ if (msg != NULL)
+ xfree(msg);
+ if (lang != NULL)
+ xfree(lang);
}
+ packet_check_eom();
+ /* Schedule the channel for cleanup/deletion. */
+ chan_mark_dead(c);
}
+/* ARGSUSED */
void
-channel_input_window_adjust(int type, int plen)
+channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
{
Channel *c;
- int id, adjust;
+ int id;
+ u_int adjust;
if (!compat20)
return;
id = packet_get_int();
c = channel_lookup(id);
- if (c == NULL || c->type != SSH_CHANNEL_OPEN) {
- log("Received window adjust for "
- "non-open channel %d.", id);
+ if (c == NULL) {
+ logit("Received window adjust for non-open channel %d.", id);
return;
}
adjust = packet_get_int();
- packet_done();
- debug("channel %d: rcvd adjust %d", id, adjust);
+ packet_check_eom();
+ debug2("channel %d: rcvd adjust %u", id, adjust);
c->remote_window += adjust;
}
-/*
- * Stops listening for channels, and removes any unix domain sockets that we
- * might have.
- */
-
+/* ARGSUSED */
void
-channel_stop_listening()
+channel_input_port_open(int type, u_int32_t seq, void *ctxt)
{
- int i;
- for (i = 0; i < channels_alloc; i++) {
- switch (channels[i].type) {
- case SSH_CHANNEL_AUTH_SOCKET:
- close(channels[i].sock);
- remove(channels[i].path);
- channel_free(i);
- break;
- case SSH_CHANNEL_PORT_LISTENER:
- case SSH_CHANNEL_X11_LISTENER:
- close(channels[i].sock);
- channel_free(i);
- break;
- default:
- break;
- }
- }
-}
+ Channel *c = NULL;
+ u_short host_port;
+ char *host, *originator_string;
+ int remote_id;
-/*
- * Closes the sockets/fds of all channels. This is used to close extra file
- * descriptors after a fork.
- */
+ remote_id = packet_get_int();
+ host = packet_get_string(NULL);
+ host_port = packet_get_int();
+
+ if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
+ originator_string = packet_get_string(NULL);
+ } else {
+ originator_string = xstrdup("unknown (remote did not supply name)");
+ }
+ packet_check_eom();
+ c = channel_connect_to(host, host_port,
+ "connected socket", originator_string);
+ xfree(originator_string);
+ xfree(host);
+ if (c == NULL) {
+ packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
+ packet_put_int(remote_id);
+ packet_send();
+ } else
+ c->remote_id = remote_id;
+}
+/* ARGSUSED */
void
-channel_close_all()
+channel_input_status_confirm(int type, u_int32_t seq, void *ctxt)
{
- int i;
- for (i = 0; i < channels_alloc; i++)
- if (channels[i].type != SSH_CHANNEL_FREE)
- channel_close_fds(&channels[i]);
-}
+ Channel *c;
+ struct channel_confirm *cc;
+ int id;
-/* Returns the maximum file descriptor number used by the channels. */
+ /* Reset keepalive timeout */
+ packet_set_alive_timeouts(0);
-int
-channel_max_fd()
-{
- return channel_max_fd_value;
-}
+ id = packet_get_int();
+ packet_check_eom();
-/* Returns true if any channel is still open. */
+ debug2("channel_input_status_confirm: type %d id %d", type, id);
-int
-channel_still_open()
-{
- unsigned int i;
- for (i = 0; i < channels_alloc; i++)
- switch (channels[i].type) {
- case SSH_CHANNEL_FREE:
- case SSH_CHANNEL_X11_LISTENER:
- case SSH_CHANNEL_PORT_LISTENER:
- case SSH_CHANNEL_CLOSED:
- case SSH_CHANNEL_AUTH_SOCKET:
- continue;
- case SSH_CHANNEL_LARVAL:
- if (!compat20)
- fatal("cannot happen: SSH_CHANNEL_LARVAL");
- continue;
- case SSH_CHANNEL_OPENING:
- case SSH_CHANNEL_OPEN:
- case SSH_CHANNEL_X11_OPEN:
- return 1;
- case SSH_CHANNEL_INPUT_DRAINING:
- case SSH_CHANNEL_OUTPUT_DRAINING:
- if (!compat13)
- fatal("cannot happen: OUT_DRAIN");
- return 1;
- default:
- fatal("channel_still_open: bad channel type %d", channels[i].type);
- /* NOTREACHED */
- }
- return 0;
+ if ((c = channel_lookup(id)) == NULL) {
+ logit("channel_input_status_confirm: %d: unknown", id);
+ return;
+ }
+ ;
+ if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
+ return;
+ cc->cb(type, c, cc->ctx);
+ TAILQ_REMOVE(&c->status_confirms, cc, entry);
+ bzero(cc, sizeof(*cc));
+ xfree(cc);
}
-/*
- * Returns a message describing the currently open forwarded connections,
- * suitable for sending to the client. The message contains crlf pairs for
- * newlines.
- */
+/* -- tcp forwarding */
-char *
-channel_open_message()
+void
+channel_set_af(int af)
{
- Buffer buffer;
- int i;
- char buf[512], *cp;
-
- buffer_init(&buffer);
- snprintf(buf, sizeof buf, "The following connections are open:\r\n");
- buffer_append(&buffer, buf, strlen(buf));
- for (i = 0; i < channels_alloc; i++) {
- Channel *c = &channels[i];
- switch (c->type) {
- case SSH_CHANNEL_FREE:
- case SSH_CHANNEL_X11_LISTENER:
- case SSH_CHANNEL_PORT_LISTENER:
- case SSH_CHANNEL_CLOSED:
- case SSH_CHANNEL_AUTH_SOCKET:
- continue;
- case SSH_CHANNEL_LARVAL:
- case SSH_CHANNEL_OPENING:
- case SSH_CHANNEL_OPEN:
- case SSH_CHANNEL_X11_OPEN:
- case SSH_CHANNEL_INPUT_DRAINING:
- case SSH_CHANNEL_OUTPUT_DRAINING:
- snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n",
- c->self, c->remote_name,
- c->type, c->remote_id,
- c->istate, buffer_len(&c->input),
- c->ostate, buffer_len(&c->output),
- c->rfd, c->wfd);
- buffer_append(&buffer, buf, strlen(buf));
- continue;
- default:
- fatal("channel_open_message: bad channel type %d", c->type);
- /* NOTREACHED */
- }
- }
- buffer_append(&buffer, "\0", 1);
- cp = xstrdup(buffer_ptr(&buffer));
- buffer_free(&buffer);
- return cp;
+ IPv4or6 = af;
}
-/*
- * Initiate forwarding of connections to local port "port" through the secure
- * channel to host:port from remote side.
- */
-
-void
-channel_request_local_forwarding(u_short port, const char *host,
- u_short host_port, int gateway_ports)
+static int
+channel_setup_fwd_listener(int type, const char *listen_addr,
+ u_short listen_port, int *allocated_listen_port,
+ const char *host_to_connect, u_short port_to_connect, int gateway_ports)
{
- int success, ch, sock, on = 1;
+ Channel *c;
+ int sock, r, success = 0, wildcard = 0, is_client;
struct addrinfo hints, *ai, *aitop;
+ const char *host, *addr;
char ntop[NI_MAXHOST], strport[NI_MAXSERV];
- struct linger linger;
+ in_port_t *lport_p;
+
+ host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
+ listen_addr : host_to_connect;
+ is_client = (type == SSH_CHANNEL_PORT_LISTENER);
- if (strlen(host) > sizeof(channels[0].path) - 1)
- packet_disconnect("Forward host name too long.");
+ if (host == NULL) {
+ error("No forward host name.");
+ return 0;
+ }
+ if (strlen(host) >= NI_MAXHOST) {
+ error("Forward host name too long.");
+ return 0;
+ }
+
+ /*
+ * Determine whether or not a port forward listens to loopback,
+ * specified address or wildcard. On the client, a specified bind
+ * address will always override gateway_ports. On the server, a
+ * gateway_ports of 1 (``yes'') will override the client's
+ * specification and force a wildcard bind, whereas a value of 2
+ * (``clientspecified'') will bind to whatever address the client
+ * asked for.
+ *
+ * Special-case listen_addrs are:
+ *
+ * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
+ * "" (empty string), "*" -> wildcard v4/v6
+ * "localhost" -> loopback v4/v6
+ */
+ addr = NULL;
+ if (listen_addr == NULL) {
+ /* No address specified: default to gateway_ports setting */
+ if (gateway_ports)
+ wildcard = 1;
+ } else if (gateway_ports || is_client) {
+ if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
+ strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
+ *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
+ (!is_client && gateway_ports == 1))
+ wildcard = 1;
+ else if (strcmp(listen_addr, "localhost") != 0)
+ addr = listen_addr;
+ }
+
+ debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s",
+ type, wildcard, (addr == NULL) ? "NULL" : addr);
/*
* getaddrinfo returns a loopback address if the hostname is
*/
memset(&hints, 0, sizeof(hints));
hints.ai_family = IPv4or6;
- hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
+ hints.ai_flags = wildcard ? AI_PASSIVE : 0;
hints.ai_socktype = SOCK_STREAM;
- snprintf(strport, sizeof strport, "%d", port);
- if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
- packet_disconnect("getaddrinfo: fatal error");
-
- success = 0;
+ snprintf(strport, sizeof strport, "%d", listen_port);
+ if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
+ if (addr == NULL) {
+ /* This really shouldn't happen */
+ packet_disconnect("getaddrinfo: fatal error: %s",
+ ssh_gai_strerror(r));
+ } else {
+ error("channel_setup_fwd_listener: "
+ "getaddrinfo(%.64s): %s", addr,
+ ssh_gai_strerror(r));
+ }
+ return 0;
+ }
+ if (allocated_listen_port != NULL)
+ *allocated_listen_port = 0;
for (ai = aitop; ai; ai = ai->ai_next) {
- if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
+ switch (ai->ai_family) {
+ case AF_INET:
+ lport_p = &((struct sockaddr_in *)ai->ai_addr)->
+ sin_port;
+ break;
+ case AF_INET6:
+ lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
+ sin6_port;
+ break;
+ default:
continue;
+ }
+ /*
+ * If allocating a port for -R forwards, then use the
+ * same port for all address families.
+ */
+ if (type == SSH_CHANNEL_RPORT_LISTENER && listen_port == 0 &&
+ allocated_listen_port != NULL && *allocated_listen_port > 0)
+ *lport_p = htons(*allocated_listen_port);
+
if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
- error("channel_request_local_forwarding: getnameinfo failed");
+ error("channel_setup_fwd_listener: getnameinfo failed");
continue;
}
/* Create a port to listen for the host. */
- sock = socket(ai->ai_family, SOCK_STREAM, 0);
+ sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
if (sock < 0) {
/* this is no error since kernel may not support ipv6 */
verbose("socket: %.100s", strerror(errno));
continue;
}
- /*
- * Set socket options. We would like the socket to disappear
- * as soon as it has been closed for whatever reason.
- */
- setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on));
- linger.l_onoff = 1;
- linger.l_linger = 5;
- setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger));
- debug("Local forwarding listening on %s port %s.", ntop, strport);
+
+ channel_set_reuseaddr(sock);
+ if (ai->ai_family == AF_INET6)
+ sock_set_v6only(sock);
+
+ debug("Local forwarding listening on %s port %s.",
+ ntop, strport);
/* Bind the socket to the address. */
if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
error("bind: %.100s", strerror(errno));
else
verbose("bind: %.100s", strerror(errno));
-
+
close(sock);
continue;
}
/* Start listening for connections on the socket. */
- if (listen(sock, 5) < 0) {
+ if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
error("listen: %.100s", strerror(errno));
close(sock);
continue;
}
+
+ /*
+ * listen_port == 0 requests a dynamically allocated port -
+ * record what we got.
+ */
+ if (type == SSH_CHANNEL_RPORT_LISTENER && listen_port == 0 &&
+ allocated_listen_port != NULL &&
+ *allocated_listen_port == 0) {
+ *allocated_listen_port = get_sock_port(sock, 1);
+ debug("Allocated listen port %d",
+ *allocated_listen_port);
+ }
+
/* Allocate a channel number for the socket. */
- ch = channel_new(
- "port listener", SSH_CHANNEL_PORT_LISTENER,
- sock, sock, -1,
+ c = channel_new("port listener", type, sock, sock, -1,
CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
- 0, xstrdup("port listener"));
- strlcpy(channels[ch].path, host, sizeof(channels[ch].path));
- channels[ch].host_port = host_port;
- channels[ch].listening_port = port;
+ 0, "port listener", 1);
+ c->path = xstrdup(host);
+ c->host_port = port_to_connect;
+ c->listening_port = listen_port;
success = 1;
}
if (success == 0)
- packet_disconnect("cannot listen port: %d", port);
+ error("channel_setup_fwd_listener: cannot listen to port: %d",
+ listen_port);
freeaddrinfo(aitop);
+ return success;
+}
+
+int
+channel_cancel_rport_listener(const char *host, u_short port)
+{
+ u_int i;
+ int found = 0;
+
+ for (i = 0; i < channels_alloc; i++) {
+ Channel *c = channels[i];
+
+ if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER &&
+ strcmp(c->path, host) == 0 && c->listening_port == port) {
+ debug2("%s: close channel %d", __func__, i);
+ channel_free(c);
+ found = 1;
+ }
+ }
+
+ return (found);
+}
+
+/* protocol local port fwd, used by ssh (and sshd in v1) */
+int
+channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port,
+ const char *host_to_connect, u_short port_to_connect, int gateway_ports)
+{
+ return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
+ listen_host, listen_port, NULL, host_to_connect, port_to_connect,
+ gateway_ports);
+}
+
+/* protocol v2 remote port fwd, used by sshd */
+int
+channel_setup_remote_fwd_listener(const char *listen_address,
+ u_short listen_port, int *allocated_listen_port, int gateway_ports)
+{
+ return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER,
+ listen_address, listen_port, allocated_listen_port,
+ NULL, 0, gateway_ports);
}
/*
* the secure channel to host:port from local side.
*/
-void
-channel_request_remote_forwarding(u_short listen_port, const char *host_to_connect,
- u_short port_to_connect)
+int
+channel_request_remote_forwarding(const char *listen_host, u_short listen_port,
+ const char *host_to_connect, u_short port_to_connect)
{
- int payload_len;
+ int type, success = 0;
+
/* Record locally that connection to this host/port is permitted. */
if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
fatal("channel_request_remote_forwarding: too many forwards");
- permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
- permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
- permitted_opens[num_permitted_opens].listen_port = listen_port;
- num_permitted_opens++;
-
/* Send the forward request to the remote side. */
if (compat20) {
- const char *address_to_bind = "0.0.0.0";
+ const char *address_to_bind;
+ if (listen_host == NULL) {
+ if (datafellows & SSH_BUG_RFWD_ADDR)
+ address_to_bind = "127.0.0.1";
+ else
+ address_to_bind = "localhost";
+ } else if (*listen_host == '\0' ||
+ strcmp(listen_host, "*") == 0) {
+ if (datafellows & SSH_BUG_RFWD_ADDR)
+ address_to_bind = "0.0.0.0";
+ else
+ address_to_bind = "";
+ } else
+ address_to_bind = listen_host;
+
packet_start(SSH2_MSG_GLOBAL_REQUEST);
packet_put_cstring("tcpip-forward");
- packet_put_char(0); /* boolean: want reply */
+ packet_put_char(1); /* boolean: want reply */
packet_put_cstring(address_to_bind);
packet_put_int(listen_port);
+ packet_send();
+ packet_write_wait();
+ /* Assume that server accepts the request */
+ success = 1;
} else {
packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
packet_put_int(listen_port);
packet_put_int(port_to_connect);
packet_send();
packet_write_wait();
- /*
- * Wait for response from the remote side. It will send a disconnect
- * message on failure, and we will never see it here.
- */
- packet_read_expect(&payload_len, SSH_SMSG_SUCCESS);
+
+ /* Wait for response from the remote side. */
+ type = packet_read();
+ switch (type) {
+ case SSH_SMSG_SUCCESS:
+ success = 1;
+ break;
+ case SSH_SMSG_FAILURE:
+ break;
+ default:
+ /* Unknown packet */
+ packet_disconnect("Protocol error for port forward request:"
+ "received packet type %d.", type);
+ }
+ }
+ if (success) {
+ permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
+ permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
+ permitted_opens[num_permitted_opens].listen_port = listen_port;
+ num_permitted_opens++;
+ }
+ return (success ? 0 : -1);
+}
+
+/*
+ * Request cancellation of remote forwarding of connection host:port from
+ * local side.
+ */
+void
+channel_request_rforward_cancel(const char *host, u_short port)
+{
+ int i;
+
+ if (!compat20)
+ return;
+
+ for (i = 0; i < num_permitted_opens; i++) {
+ if (permitted_opens[i].host_to_connect != NULL &&
+ permitted_opens[i].listen_port == port)
+ break;
+ }
+ if (i >= num_permitted_opens) {
+ debug("%s: requested forward not found", __func__);
+ return;
}
+ packet_start(SSH2_MSG_GLOBAL_REQUEST);
+ packet_put_cstring("cancel-tcpip-forward");
+ packet_put_char(0);
+ packet_put_cstring(host == NULL ? "" : host);
+ packet_put_int(port);
+ packet_send();
+
+ permitted_opens[i].listen_port = 0;
+ permitted_opens[i].port_to_connect = 0;
+ xfree(permitted_opens[i].host_to_connect);
+ permitted_opens[i].host_to_connect = NULL;
}
/*
* This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
* listening for the port, and sends back a success reply (or disconnect
- * message if there was an error). This never returns if there was an error.
+ * message if there was an error).
*/
-
-void
+int
channel_input_port_forward_request(int is_root, int gateway_ports)
{
u_short port, host_port;
+ int success = 0;
char *hostname;
/* Get arguments from the packet. */
hostname = packet_get_string(NULL);
host_port = packet_get_int();
+#ifndef HAVE_CYGWIN
/*
* Check that an unprivileged user is not trying to forward a
* privileged port.
*/
if (port < IPPORT_RESERVED && !is_root)
- packet_disconnect("Requested forwarding of port %d but user is not root.",
- port);
- /*
- * Initiate forwarding,
- */
- channel_request_local_forwarding(port, hostname, host_port, gateway_ports);
+ packet_disconnect(
+ "Requested forwarding of port %d but user is not root.",
+ port);
+ if (host_port == 0)
+ packet_disconnect("Dynamic forwarding denied.");
+#endif
+
+ /* Initiate forwarding */
+ success = channel_setup_local_fwd_listener(NULL, port, hostname,
+ host_port, gateway_ports);
/* Free the argument string. */
xfree(hostname);
+
+ return (success ? 0 : -1);
+}
+
+/*
+ * Permits opening to any host/port if permitted_opens[] is empty. This is
+ * usually called by the server, because the user could connect to any port
+ * anyway, and the server has no way to know but to trust the client anyway.
+ */
+void
+channel_permit_all_opens(void)
+{
+ if (num_permitted_opens == 0)
+ all_opens_permitted = 1;
+}
+
+void
+channel_add_permitted_opens(char *host, int port)
+{
+ if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
+ fatal("channel_add_permitted_opens: too many forwards");
+ debug("allow port forwarding to host %s port %d", host, port);
+
+ permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
+ permitted_opens[num_permitted_opens].port_to_connect = port;
+ num_permitted_opens++;
+
+ all_opens_permitted = 0;
}
-/* XXX move to aux.c */
int
-channel_connect_to(const char *host, u_short host_port)
+channel_add_adm_permitted_opens(char *host, int port)
{
- struct addrinfo hints, *ai, *aitop;
- char ntop[NI_MAXHOST], strport[NI_MAXSERV];
- int gaierr;
- int sock = -1;
+ if (num_adm_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
+ fatal("channel_add_adm_permitted_opens: too many forwards");
+ debug("config allows port forwarding to host %s port %d", host, port);
- memset(&hints, 0, sizeof(hints));
- hints.ai_family = IPv4or6;
- hints.ai_socktype = SOCK_STREAM;
- snprintf(strport, sizeof strport, "%d", host_port);
- if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
- error("%.100s: unknown host (%s)", host, gai_strerror(gaierr));
- return -1;
+ permitted_adm_opens[num_adm_permitted_opens].host_to_connect
+ = xstrdup(host);
+ permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
+ return ++num_adm_permitted_opens;
+}
+
+void
+channel_clear_permitted_opens(void)
+{
+ int i;
+
+ for (i = 0; i < num_permitted_opens; i++)
+ if (permitted_opens[i].host_to_connect != NULL)
+ xfree(permitted_opens[i].host_to_connect);
+ num_permitted_opens = 0;
+}
+
+void
+channel_clear_adm_permitted_opens(void)
+{
+ int i;
+
+ for (i = 0; i < num_adm_permitted_opens; i++)
+ if (permitted_adm_opens[i].host_to_connect != NULL)
+ xfree(permitted_adm_opens[i].host_to_connect);
+ num_adm_permitted_opens = 0;
+}
+
+void
+channel_print_adm_permitted_opens(void)
+{
+ int i;
+
+ printf("permitopen");
+ if (num_adm_permitted_opens == 0) {
+ printf(" any\n");
+ return;
}
- for (ai = aitop; ai; ai = ai->ai_next) {
- if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
+ for (i = 0; i < num_adm_permitted_opens; i++)
+ if (permitted_adm_opens[i].host_to_connect != NULL)
+ printf(" %s:%d", permitted_adm_opens[i].host_to_connect,
+ permitted_adm_opens[i].port_to_connect);
+ printf("\n");
+}
+
+/* Try to start non-blocking connect to next host in cctx list */
+static int
+connect_next(struct channel_connect *cctx)
+{
+ int sock, saved_errno;
+ char ntop[NI_MAXHOST], strport[NI_MAXSERV];
+
+ for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
+ if (cctx->ai->ai_family != AF_INET &&
+ cctx->ai->ai_family != AF_INET6)
continue;
- if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
- strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
- error("channel_connect_to: getnameinfo failed");
+ if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
+ ntop, sizeof(ntop), strport, sizeof(strport),
+ NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
+ error("connect_next: getnameinfo failed");
continue;
}
- /* Create the socket. */
- sock = socket(ai->ai_family, SOCK_STREAM, 0);
- if (sock < 0) {
- error("socket: %.100s", strerror(errno));
+ if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
+ cctx->ai->ai_protocol)) == -1) {
+ if (cctx->ai->ai_next == NULL)
+ error("socket: %.100s", strerror(errno));
+ else
+ verbose("socket: %.100s", strerror(errno));
continue;
}
- /* Connect to the host/port. */
- if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
- error("connect %.100s port %s: %.100s", ntop, strport,
+ if (set_nonblock(sock) == -1)
+ fatal("%s: set_nonblock(%d)", __func__, sock);
+ if (connect(sock, cctx->ai->ai_addr,
+ cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
+ debug("connect_next: host %.100s ([%.100s]:%s): "
+ "%.100s", cctx->host, ntop, strport,
strerror(errno));
+ saved_errno = errno;
close(sock);
- continue; /* fail -- try next */
+ errno = saved_errno;
+ continue; /* fail -- try next */
}
- break; /* success */
+ debug("connect_next: host %.100s ([%.100s]:%s) "
+ "in progress, fd=%d", cctx->host, ntop, strport, sock);
+ cctx->ai = cctx->ai->ai_next;
+ set_nodelay(sock);
+ return sock;
+ }
+ return -1;
+}
+
+static void
+channel_connect_ctx_free(struct channel_connect *cctx)
+{
+ xfree(cctx->host);
+ if (cctx->aitop)
+ freeaddrinfo(cctx->aitop);
+ bzero(cctx, sizeof(*cctx));
+ cctx->host = NULL;
+ cctx->ai = cctx->aitop = NULL;
+}
+
+/* Return CONNECTING channel to remote host, port */
+static Channel *
+connect_to(const char *host, u_short port, char *ctype, char *rname)
+{
+ struct addrinfo hints;
+ int gaierr;
+ int sock = -1;
+ char strport[NI_MAXSERV];
+ struct channel_connect cctx;
+ Channel *c;
+ memset(&cctx, 0, sizeof(cctx));
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = IPv4or6;
+ hints.ai_socktype = SOCK_STREAM;
+ snprintf(strport, sizeof strport, "%d", port);
+ if ((gaierr = getaddrinfo(host, strport, &hints, &cctx.aitop)) != 0) {
+ error("connect_to %.100s: unknown host (%s)", host,
+ ssh_gai_strerror(gaierr));
+ return NULL;
}
- freeaddrinfo(aitop);
- if (!ai) {
- error("connect %.100s port %d: failed.", host, host_port);
- return -1;
+
+ cctx.host = xstrdup(host);
+ cctx.port = port;
+ cctx.ai = cctx.aitop;
+
+ if ((sock = connect_next(&cctx)) == -1) {
+ error("connect to %.100s port %d failed: %s",
+ host, port, strerror(errno));
+ channel_connect_ctx_free(&cctx);
+ return NULL;
}
- /* success */
- return sock;
+ c = channel_new(ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
+ CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
+ c->connect_ctx = cctx;
+ return c;
}
-/*
- * This is called after receiving PORT_OPEN message. This attempts to
- * connect to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION
- * or CHANNEL_OPEN_FAILURE.
- */
-
-void
-channel_input_port_open(int type, int plen)
+Channel *
+channel_connect_by_listen_address(u_short listen_port, char *ctype, char *rname)
{
- u_short host_port;
- char *host, *originator_string;
- int remote_channel, sock = -1, newch, i, denied;
- unsigned int host_len, originator_len;
-
- /* Get remote channel number. */
- remote_channel = packet_get_int();
-
- /* Get host name to connect to. */
- host = packet_get_string(&host_len);
-
- /* Get port to connect to. */
- host_port = packet_get_int();
+ int i;
- /* Get remote originator name. */
- if (have_hostname_in_open) {
- originator_string = packet_get_string(&originator_len);
- originator_len += 4; /* size of packet_int */
- } else {
- originator_string = xstrdup("unknown (remote did not supply name)");
- originator_len = 0; /* no originator supplied */
+ for (i = 0; i < num_permitted_opens; i++) {
+ if (permitted_opens[i].host_to_connect != NULL &&
+ permitted_opens[i].listen_port == listen_port) {
+ return connect_to(
+ permitted_opens[i].host_to_connect,
+ permitted_opens[i].port_to_connect, ctype, rname);
+ }
}
+ error("WARNING: Server requests forwarding for unknown listen_port %d",
+ listen_port);
+ return NULL;
+}
- packet_integrity_check(plen,
- 4 + 4 + host_len + 4 + originator_len, SSH_MSG_PORT_OPEN);
+/* Check if connecting to that port is permitted and connect. */
+Channel *
+channel_connect_to(const char *host, u_short port, char *ctype, char *rname)
+{
+ int i, permit, permit_adm = 1;
- /* Check if opening that port is permitted. */
- denied = 0;
- if (!all_opens_permitted) {
- /* Go trough all permitted ports. */
+ permit = all_opens_permitted;
+ if (!permit) {
for (i = 0; i < num_permitted_opens; i++)
- if (permitted_opens[i].port_to_connect == host_port &&
+ if (permitted_opens[i].host_to_connect != NULL &&
+ permitted_opens[i].port_to_connect == port &&
strcmp(permitted_opens[i].host_to_connect, host) == 0)
- break;
+ permit = 1;
+ }
- /* Check if we found the requested port among those permitted. */
- if (i >= num_permitted_opens) {
- /* The port is not permitted. */
- log("Received request to connect to %.100s:%d, but the request was denied.",
- host, host_port);
- denied = 1;
- }
+ if (num_adm_permitted_opens > 0) {
+ permit_adm = 0;
+ for (i = 0; i < num_adm_permitted_opens; i++)
+ if (permitted_adm_opens[i].host_to_connect != NULL &&
+ permitted_adm_opens[i].port_to_connect == port &&
+ strcmp(permitted_adm_opens[i].host_to_connect, host)
+ == 0)
+ permit_adm = 1;
}
- sock = denied ? -1 : channel_connect_to(host, host_port);
- if (sock > 0) {
- /* Allocate a channel for this connection. */
- newch = channel_allocate(SSH_CHANNEL_OPEN, sock, originator_string);
- channels[newch].remote_id = remote_channel;
- packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
- packet_put_int(remote_channel);
- packet_put_int(newch);
- packet_send();
- } else {
- packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
- packet_put_int(remote_channel);
+ if (!permit || !permit_adm) {
+ logit("Received request to connect to host %.100s port %d, "
+ "but the request was denied.", host, port);
+ return NULL;
+ }
+ return connect_to(host, port, ctype, rname);
+}
+
+void
+channel_send_window_changes(void)
+{
+ u_int i;
+ struct winsize ws;
+
+ for (i = 0; i < channels_alloc; i++) {
+ if (channels[i] == NULL || !channels[i]->client_tty ||
+ channels[i]->type != SSH_CHANNEL_OPEN)
+ continue;
+ if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
+ continue;
+ channel_request_start(i, "window-change", 0);
+ packet_put_int((u_int)ws.ws_col);
+ packet_put_int((u_int)ws.ws_row);
+ packet_put_int((u_int)ws.ws_xpixel);
+ packet_put_int((u_int)ws.ws_ypixel);
packet_send();
}
- xfree(host);
}
+/* -- X11 forwarding */
+
/*
* Creates an internet domain socket for listening for X11 connections.
- * Returns a suitable value for the DISPLAY variable, or NULL if an error
- * occurs.
+ * Returns 0 and a suitable display number for the DISPLAY variable
+ * stored in display_numberp , or -1 if an error occurs.
*/
-
-#define NUM_SOCKS 10
-
-char *
-x11_create_display_inet(int screen_number, int x11_display_offset)
+int
+x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
+ int single_connection, u_int *display_numberp, int **chanids)
{
+ Channel *nc = NULL;
int display_number, sock;
u_short port;
struct addrinfo hints, *ai, *aitop;
char strport[NI_MAXSERV];
int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
- char display[512];
- char hostname[MAXHOSTNAMELEN];
+
+ if (chanids == NULL)
+ return -1;
for (display_number = x11_display_offset;
- display_number < MAX_DISPLAYS;
- display_number++) {
+ display_number < MAX_DISPLAYS;
+ display_number++) {
port = 6000 + display_number;
memset(&hints, 0, sizeof(hints));
hints.ai_family = IPv4or6;
- hints.ai_flags = AI_PASSIVE; /* XXX loopback only ? */
+ hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
hints.ai_socktype = SOCK_STREAM;
snprintf(strport, sizeof strport, "%d", port);
if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
- error("getaddrinfo: %.100s", gai_strerror(gaierr));
- return NULL;
+ error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
+ return -1;
}
for (ai = aitop; ai; ai = ai->ai_next) {
if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
continue;
- sock = socket(ai->ai_family, SOCK_STREAM, 0);
+ sock = socket(ai->ai_family, ai->ai_socktype,
+ ai->ai_protocol);
if (sock < 0) {
- if (errno != EINVAL) {
+ if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) {
error("socket: %.100s", strerror(errno));
- return NULL;
+ freeaddrinfo(aitop);
+ return -1;
} else {
- debug("Socket family %d not supported [X11 disp create]", ai->ai_family);
+ debug("x11_create_display_inet: Socket family %d not supported",
+ ai->ai_family);
continue;
}
}
+ if (ai->ai_family == AF_INET6)
+ sock_set_v6only(sock);
+ if (x11_use_localhost)
+ channel_set_reuseaddr(sock);
if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
- debug("bind port %d: %.100s", port, strerror(errno));
- shutdown(sock, SHUT_RDWR);
+ debug2("bind port %d: %.100s", port, strerror(errno));
close(sock);
- if (ai->ai_next)
- continue;
-
for (n = 0; n < num_socks; n++) {
- shutdown(socks[n], SHUT_RDWR);
close(socks[n]);
}
num_socks = 0;
break;
}
socks[num_socks++] = sock;
-#ifndef DONT_TRY_OTHER_AF
if (num_socks == NUM_SOCKS)
break;
-#else
- break;
-#endif
}
+ freeaddrinfo(aitop);
if (num_socks > 0)
break;
}
if (display_number >= MAX_DISPLAYS) {
error("Failed to allocate internet-domain X11 display socket.");
- return NULL;
+ return -1;
}
/* Start listening for connections on the socket. */
for (n = 0; n < num_socks; n++) {
sock = socks[n];
- if (listen(sock, 5) < 0) {
+ if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
error("listen: %.100s", strerror(errno));
- shutdown(sock, SHUT_RDWR);
- close(sock);
- return NULL;
- }
- }
-
- /* Set up a suitable value for the DISPLAY variable. */
-
- if (gethostname(hostname, sizeof(hostname)) < 0)
- fatal("gethostname: %.100s", strerror(errno));
-
-#ifdef IPADDR_IN_DISPLAY
- /*
- * HPUX detects the local hostname in the DISPLAY variable and tries
- * to set up a shared memory connection to the server, which it
- * incorrectly supposes to be local.
- *
- * The workaround - as used in later $$H and other programs - is
- * is to set display to the host's IP address.
- */
- {
- struct hostent *he;
- struct in_addr my_addr;
-
- he = gethostbyname(hostname);
- if (he == NULL) {
- error("[X11-broken-fwd-hostname-workaround] Could not get "
- "IP address for hostname %s.", hostname);
-
- packet_send_debug("[X11-broken-fwd-hostname-workaround]"
- "Could not get IP address for hostname %s.", hostname);
-
- shutdown(sock, SHUT_RDWR);
close(sock);
-
- return NULL;
+ return -1;
}
-
- memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr));
-
- /* Set DISPLAY to <ip address>:screen.display */
- snprintf(display, sizeof(display), "%.50s:%d.%d", inet_ntoa(my_addr),
- display_number, screen_number);
}
-#else /* IPADDR_IN_DISPLAY */
- /* Just set DISPLAY to hostname:screen.display */
- snprintf(display, sizeof display, "%.400s:%d.%d", hostname,
- display_number, screen_number);
-#endif /* IPADDR_IN_DISPLAY */
/* Allocate a channel for each socket. */
+ *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
for (n = 0; n < num_socks; n++) {
sock = socks[n];
- (void) channel_new("x11 listener",
+ nc = channel_new("x11 listener",
SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
- 0, xstrdup("X11 inet listener"));
+ 0, "X11 inet listener", 1);
+ nc->single_connection = single_connection;
+ (*chanids)[n] = nc->self;
}
+ (*chanids)[n] = -1;
- /* Return a suitable value for the DISPLAY environment variable. */
- return xstrdup(display);
+ /* Return the display number for the DISPLAY environment variable. */
+ *display_numberp = display_number;
+ return (0);
}
-#ifndef X_UNIX_PATH
-#define X_UNIX_PATH "/tmp/.X11-unix/X"
-#endif
-
-static
-int
-connect_local_xsocket(unsigned int dnr)
-{
- static const char *const x_sockets[] = {
- X_UNIX_PATH "%u",
- "/var/X/.X11-unix/X" "%u",
- "/usr/spool/sockets/X11/" "%u",
- NULL
- };
+static int
+connect_local_xsocket_path(const char *pathname)
+{
int sock;
struct sockaddr_un addr;
- const char *const * path;
- for (path = x_sockets; *path; ++path) {
- sock = socket(AF_UNIX, SOCK_STREAM, 0);
- if (sock < 0)
- error("socket: %.100s", strerror(errno));
- memset(&addr, 0, sizeof(addr));
- addr.sun_family = AF_UNIX;
- snprintf(addr.sun_path, sizeof addr.sun_path, *path, dnr);
- if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0)
- return sock;
- close(sock);
- }
+ sock = socket(AF_UNIX, SOCK_STREAM, 0);
+ if (sock < 0)
+ error("socket: %.100s", strerror(errno));
+ memset(&addr, 0, sizeof(addr));
+ addr.sun_family = AF_UNIX;
+ strlcpy(addr.sun_path, pathname, sizeof addr.sun_path);
+ if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
+ return sock;
+ close(sock);
error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
return -1;
}
+static int
+connect_local_xsocket(u_int dnr)
+{
+ char buf[1024];
+ snprintf(buf, sizeof buf, _PATH_UNIX_X, dnr);
+ return connect_local_xsocket_path(buf);
+}
+
int
x11_connect_display(void)
{
- int display_number, sock = 0;
+ u_int display_number;
const char *display;
char buf[1024], *cp;
struct addrinfo hints, *ai, *aitop;
char strport[NI_MAXSERV];
- int gaierr;
+ int gaierr, sock = 0;
/* Try to open a socket for the local X server. */
display = getenv("DISPLAY");
* connection to the real X server.
*/
+ /* Check if the display is from launchd. */
+#ifdef __APPLE__
+ if (strncmp(display, "/tmp/launch", 11) == 0) {
+ sock = connect_local_xsocket_path(display);
+ if (sock < 0)
+ return -1;
+
+ /* OK, we now have a connection to the display. */
+ return sock;
+ }
+#endif
/*
* Check if it is a unix domain socket. Unix domain displays are in
* one of the following formats: unix:d[.s], :d[.s], ::d[.s]
if (strncmp(display, "unix:", 5) == 0 ||
display[0] == ':') {
/* Connect to the unix domain socket. */
- if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) {
+ if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
error("Could not parse display number from DISPLAY: %.100s",
- display);
+ display);
return -1;
}
/* Create a socket. */
* Connect to an inet socket. The DISPLAY value is supposedly
* hostname:d[.s], where hostname may also be numeric IP address.
*/
- strncpy(buf, display, sizeof(buf));
- buf[sizeof(buf) - 1] = 0;
+ strlcpy(buf, display, sizeof(buf));
cp = strchr(buf, ':');
if (!cp) {
error("Could not find ':' in DISPLAY: %.100s", display);
}
*cp = 0;
/* buf now contains the host name. But first we parse the display number. */
- if (sscanf(cp + 1, "%d", &display_number) != 1) {
+ if (sscanf(cp + 1, "%u", &display_number) != 1) {
error("Could not parse display number from DISPLAY: %.100s",
- display);
+ display);
return -1;
}
memset(&hints, 0, sizeof(hints));
hints.ai_family = IPv4or6;
hints.ai_socktype = SOCK_STREAM;
- snprintf(strport, sizeof strport, "%d", 6000 + display_number);
+ snprintf(strport, sizeof strport, "%u", 6000 + display_number);
if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
- error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
+ error("%.100s: unknown host. (%s)", buf,
+ ssh_gai_strerror(gaierr));
return -1;
}
for (ai = aitop; ai; ai = ai->ai_next) {
/* Create a socket. */
- sock = socket(ai->ai_family, SOCK_STREAM, 0);
+ sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
if (sock < 0) {
- debug("socket: %.100s", strerror(errno));
+ debug2("socket: %.100s", strerror(errno));
continue;
}
/* Connect it to the display. */
if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
- debug("connect %.100s port %d: %.100s", buf,
+ debug2("connect %.100s port %u: %.100s", buf,
6000 + display_number, strerror(errno));
close(sock);
continue;
}
freeaddrinfo(aitop);
if (!ai) {
- error("connect %.100s port %d: %.100s", buf, 6000 + display_number,
+ error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
strerror(errno));
return -1;
}
+ set_nodelay(sock);
return sock;
}
* with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
*/
+/* ARGSUSED */
void
-x11_input_open(int type, int plen)
+x11_input_open(int type, u_int32_t seq, void *ctxt)
{
- int remote_channel, sock = 0, newch;
+ Channel *c = NULL;
+ int remote_id, sock = 0;
char *remote_host;
- unsigned int remote_len;
- /* Get remote channel number. */
- remote_channel = packet_get_int();
+ debug("Received X11 open request.");
+
+ remote_id = packet_get_int();
- /* Get remote originator name. */
- if (have_hostname_in_open) {
- remote_host = packet_get_string(&remote_len);
- remote_len += 4;
+ if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
+ remote_host = packet_get_string(NULL);
} else {
remote_host = xstrdup("unknown (remote did not supply name)");
- remote_len = 0;
}
-
- debug("Received X11 open request.");
- packet_integrity_check(plen, 4 + remote_len, SSH_SMSG_X11_OPEN);
+ packet_check_eom();
/* Obtain a connection to the real X display. */
sock = x11_connect_display();
- if (sock == -1) {
+ if (sock != -1) {
+ /* Allocate a channel for this connection. */
+ c = channel_new("connected x11 socket",
+ SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
+ remote_host, 1);
+ c->remote_id = remote_id;
+ c->force_drain = 1;
+ }
+ xfree(remote_host);
+ if (c == NULL) {
/* Send refusal to the remote host. */
packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
- packet_put_int(remote_channel);
- packet_send();
+ packet_put_int(remote_id);
} else {
- /* Allocate a channel for this connection. */
- newch = channel_allocate(
- (x11_saved_proto == NULL) ?
- SSH_CHANNEL_OPEN : SSH_CHANNEL_X11_OPEN,
- sock, remote_host);
- channels[newch].remote_id = remote_channel;
-
/* Send a confirmation to the remote host. */
packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
- packet_put_int(remote_channel);
- packet_put_int(newch);
- packet_send();
+ packet_put_int(remote_id);
+ packet_put_int(c->self);
+ }
+ packet_send();
+}
+
+/* dummy protocol handler that denies SSH-1 requests (agent/x11) */
+/* ARGSUSED */
+void
+deny_input_open(int type, u_int32_t seq, void *ctxt)
+{
+ int rchan = packet_get_int();
+
+ switch (type) {
+ case SSH_SMSG_AGENT_OPEN:
+ error("Warning: ssh server tried agent forwarding.");
+ break;
+ case SSH_SMSG_X11_OPEN:
+ error("Warning: ssh server tried X11 forwarding.");
+ break;
+ default:
+ error("deny_input_open: type %d", type);
+ break;
}
+ error("Warning: this is probably a break-in attempt by a malicious server.");
+ packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
+ packet_put_int(rchan);
+ packet_send();
}
/*
* Requests forwarding of X11 connections, generates fake authentication
* data, and enables authentication spoofing.
+ * This should be called in the client only.
*/
-
void
-x11_request_forwarding_with_spoofing(int client_session_id,
+x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
const char *proto, const char *data)
{
- unsigned int data_len = (unsigned int) strlen(data) / 2;
- unsigned int i, value;
+ u_int data_len = (u_int) strlen(data) / 2;
+ u_int i, value;
char *new_data;
int screen_number;
const char *cp;
- u_int32_t rand = 0;
+ u_int32_t rnd = 0;
- cp = getenv("DISPLAY");
- if (cp)
- cp = strchr(cp, ':');
+ if (x11_saved_display == NULL)
+ x11_saved_display = xstrdup(disp);
+ else if (strcmp(disp, x11_saved_display) != 0) {
+ error("x11_request_forwarding_with_spoofing: different "
+ "$DISPLAY already forwarded");
+ return;
+ }
+
+ cp = strchr(disp, ':');
if (cp)
cp = strchr(cp, '.');
if (cp)
- screen_number = atoi(cp + 1);
+ screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
else
screen_number = 0;
- /* Save protocol name. */
- x11_saved_proto = xstrdup(proto);
-
- /*
- * Extract real authentication data and generate fake data of the
- * same length.
- */
- x11_saved_data = xmalloc(data_len);
- x11_fake_data = xmalloc(data_len);
- for (i = 0; i < data_len; i++) {
- if (sscanf(data + 2 * i, "%2x", &value) != 1)
- fatal("x11_request_forwarding: bad authentication data: %.100s", data);
- if (i % 4 == 0)
- rand = arc4random();
- x11_saved_data[i] = value;
- x11_fake_data[i] = rand & 0xff;
- rand >>= 8;
- }
- x11_saved_data_len = data_len;
- x11_fake_data_len = data_len;
+ if (x11_saved_proto == NULL) {
+ /* Save protocol name. */
+ x11_saved_proto = xstrdup(proto);
+ /*
+ * Extract real authentication data and generate fake data
+ * of the same length.
+ */
+ x11_saved_data = xmalloc(data_len);
+ x11_fake_data = xmalloc(data_len);
+ for (i = 0; i < data_len; i++) {
+ if (sscanf(data + 2 * i, "%2x", &value) != 1)
+ fatal("x11_request_forwarding: bad "
+ "authentication data: %.100s", data);
+ if (i % 4 == 0)
+ rnd = arc4random();
+ x11_saved_data[i] = value;
+ x11_fake_data[i] = rnd & 0xff;
+ rnd >>= 8;
+ }
+ x11_saved_data_len = data_len;
+ x11_fake_data_len = data_len;
+ }
/* Convert the fake data into hex. */
- new_data = xmalloc(2 * data_len + 1);
- for (i = 0; i < data_len; i++)
- sprintf(new_data + 2 * i, "%02x", (unsigned char) x11_fake_data[i]);
+ new_data = tohex(x11_fake_data, data_len);
/* Send the request packet. */
if (compat20) {
xfree(new_data);
}
+
+/* -- agent forwarding */
+
/* Sends a message to the server to request authentication fd forwarding. */
void
-auth_request_forwarding()
+auth_request_forwarding(void)
{
packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
packet_send();
packet_write_wait();
}
-
-/*
- * Returns the name of the forwarded authentication socket. Returns NULL if
- * there is no forwarded authentication socket. The returned value points to
- * a static buffer.
- */
-
-char *
-auth_get_socket_name()
-{
- return channel_forwarded_auth_socket_name;
-}
-
-/* removes the agent forwarding socket */
-
-void
-cleanup_socket(void)
-{
- remove(channel_forwarded_auth_socket_name);
- rmdir(channel_forwarded_auth_socket_dir);
-}
-
-/*
- * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
- * This starts forwarding authentication requests.
- */
-
-int
-auth_input_request_forwarding(struct passwd * pw)
-{
- int sock, newch;
- struct sockaddr_un sunaddr;
-
- if (auth_get_socket_name() != NULL)
- fatal("Protocol error: authentication forwarding requested twice.");
-
- /* Temporarily drop privileged uid for mkdir/bind. */
- temporarily_use_uid(pw->pw_uid);
-
- /* Allocate a buffer for the socket name, and format the name. */
- channel_forwarded_auth_socket_name = xmalloc(MAX_SOCKET_NAME);
- channel_forwarded_auth_socket_dir = xmalloc(MAX_SOCKET_NAME);
- strlcpy(channel_forwarded_auth_socket_dir, "/tmp/ssh-XXXXXXXX", MAX_SOCKET_NAME);
-
- /* Create private directory for socket */
- if (mkdtemp(channel_forwarded_auth_socket_dir) == NULL) {
- packet_send_debug("Agent forwarding disabled: mkdtemp() failed: %.100s",
- strerror(errno));
- restore_uid();
- xfree(channel_forwarded_auth_socket_name);
- xfree(channel_forwarded_auth_socket_dir);
- channel_forwarded_auth_socket_name = NULL;
- channel_forwarded_auth_socket_dir = NULL;
- return 0;
- }
- snprintf(channel_forwarded_auth_socket_name, MAX_SOCKET_NAME, "%s/agent.%d",
- channel_forwarded_auth_socket_dir, (int) getpid());
-
- if (atexit(cleanup_socket) < 0) {
- int saved = errno;
- cleanup_socket();
- packet_disconnect("socket: %.100s", strerror(saved));
- }
- /* Create the socket. */
- sock = socket(AF_UNIX, SOCK_STREAM, 0);
- if (sock < 0)
- packet_disconnect("socket: %.100s", strerror(errno));
-
- /* Bind it to the name. */
- memset(&sunaddr, 0, sizeof(sunaddr));
- sunaddr.sun_family = AF_UNIX;
- strncpy(sunaddr.sun_path, channel_forwarded_auth_socket_name,
- sizeof(sunaddr.sun_path));
-
- if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
- packet_disconnect("bind: %.100s", strerror(errno));
-
- /* Restore the privileged uid. */
- restore_uid();
-
- /* Start listening on the socket. */
- if (listen(sock, 5) < 0)
- packet_disconnect("listen: %.100s", strerror(errno));
-
- /* Allocate a channel for the authentication agent socket. */
- newch = channel_allocate(SSH_CHANNEL_AUTH_SOCKET, sock,
- xstrdup("auth socket"));
- strlcpy(channels[newch].path, channel_forwarded_auth_socket_name,
- sizeof(channels[newch].path));
- return 1;
-}
-
-/* This is called to process an SSH_SMSG_AGENT_OPEN message. */
-
-void
-auth_input_open_request(int type, int plen)
-{
- int remch, sock, newch;
- char *dummyname;
-
- packet_integrity_check(plen, 4, type);
-
- /* Read the remote channel number from the message. */
- remch = packet_get_int();
-
- /*
- * Get a connection to the local authentication agent (this may again
- * get forwarded).
- */
- sock = ssh_get_authentication_socket();
-
- /*
- * If we could not connect the agent, send an error message back to
- * the server. This should never happen unless the agent dies,
- * because authentication forwarding is only enabled if we have an
- * agent.
- */
- if (sock < 0) {
- packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
- packet_put_int(remch);
- packet_send();
- return;
- }
- debug("Forwarding authentication connection.");
-
- /*
- * Dummy host name. This will be freed when the channel is freed; it
- * will still be valid in the packet_put_string below since the
- * channel cannot yet be freed at that point.
- */
- dummyname = xstrdup("authentication agent connection");
-
- newch = channel_allocate(SSH_CHANNEL_OPEN, sock, dummyname);
- channels[newch].remote_id = remch;
-
- /* Send a confirmation to the remote host. */
- packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
- packet_put_int(remch);
- packet_put_int(newch);
- packet_send();
-}
-
-void
-channel_start_open(int id)
-{
- Channel *c = channel_lookup(id);
- if (c == NULL) {
- log("channel_open: %d: bad id", id);
- return;
- }
- debug("send channel open %d", id);
- packet_start(SSH2_MSG_CHANNEL_OPEN);
- packet_put_cstring(c->ctype);
- packet_put_int(c->self);
- packet_put_int(c->local_window);
- packet_put_int(c->local_maxpacket);
-}
-void
-channel_open(int id)
-{
- /* XXX REMOVE ME */
- channel_start_open(id);
- packet_send();
-}
-void
-channel_request(int id, char *service, int wantconfirm)
-{
- channel_request_start(id, service, wantconfirm);
- packet_send();
- debug("channel request %d: %s", id, service) ;
-}
-void
-channel_request_start(int id, char *service, int wantconfirm)
-{
- Channel *c = channel_lookup(id);
- if (c == NULL) {
- log("channel_request: %d: bad id", id);
- return;
- }
- packet_start(SSH2_MSG_CHANNEL_REQUEST);
- packet_put_int(c->remote_id);
- packet_put_cstring(service);
- packet_put_char(wantconfirm);
-}
-void
-channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg)
-{
- Channel *c = channel_lookup(id);
- if (c == NULL) {
- log("channel_register_callback: %d: bad id", id);
- return;
- }
- c->cb_event = mtype;
- c->cb_fn = fn;
- c->cb_arg = arg;
-}
-void
-channel_register_cleanup(int id, channel_callback_fn *fn)
-{
- Channel *c = channel_lookup(id);
- if (c == NULL) {
- log("channel_register_cleanup: %d: bad id", id);
- return;
- }
- c->dettach_user = fn;
-}
-void
-channel_cancel_cleanup(int id)
-{
- Channel *c = channel_lookup(id);
- if (c == NULL) {
- log("channel_cancel_cleanup: %d: bad id", id);
- return;
- }
- c->dettach_user = NULL;
-}
-
-void
-channel_set_fds(int id, int rfd, int wfd, int efd, int extusage)
-{
- Channel *c = channel_lookup(id);
- if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
- fatal("channel_activate for non-larval channel %d.", id);
-
- channel_register_fds(c, rfd, wfd, efd, extusage);
- c->type = SSH_CHANNEL_OPEN;
- /* XXX window size? */
- c->local_window = c->local_window_max = c->local_maxpacket/2;
- packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
- packet_put_int(c->remote_id);
- packet_put_int(c->local_window);
- packet_send();
-}
andersk / openssh.git / blobdiff