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- djm@cvs.openbsd.org 2010/01/26 01:28:35 

[channels.c channels.h clientloop.c clientloop.h mux.c nchan.c ssh.c]
     rewrite ssh(1) multiplexing code to a more sensible protocol.

     The new multiplexing code uses channels for the listener and
     accepted control sockets to make the mux master non-blocking, so
     no stalls when processing messages from a slave.

     avoid use of fatal() in mux master protocol parsing so an errant slave
     process cannot take down a running master.

     implement requesting of port-forwards over multiplexed sessions. Any
     port forwards requested by the slave are added to those the master has
     established.

     add support for stdio forwarding ("ssh -W host:port ...") in mux slaves.

     document master/slave mux protocol so that other tools can use it to
     control a running ssh(1). Note: there are no guarantees that this
     protocol won't be incompatibly changed (though it is versioned).

     feedback Salvador Fandino, dtucker@
     channel changes ok markus@
This commit is contained in:
Damien Miller 2010-01-26 13:26:22 +11:00
parent f589fd1ea8
commit e1537f951f
8 changed files with 1712 additions and 545 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
ChangeLog
View File

@ -8,6 +8,29 @@
[roaming_client.c]
s/long long unsigned/unsigned long long/, from tim via portable
(Id sync only, change already in portable)
- djm@cvs.openbsd.org 2010/01/26 01:28:35
[channels.c channels.h clientloop.c clientloop.h mux.c nchan.c ssh.c]
rewrite ssh(1) multiplexing code to a more sensible protocol.
The new multiplexing code uses channels for the listener and
accepted control sockets to make the mux master non-blocking, so
no stalls when processing messages from a slave.
avoid use of fatal() in mux master protocol parsing so an errant slave
process cannot take down a running master.
implement requesting of port-forwards over multiplexed sessions. Any
port forwards requested by the slave are added to those the master has
established.
add support for stdio forwarding ("ssh -W host:port ...") in mux slaves.
document master/slave mux protocol so that other tools can use it to
control a running ssh(1). Note: there are no guarantees that this
protocol won't be incompatibly changed (though it is versioned).
feedback Salvador Fandino, dtucker@
channel changes ok markus@
20100122
- (tim) [configure.ac] Due to constraints in Windows Sockets in terms of

214
channels.c
View File

@ -1,4 +1,4 @@
/* $OpenBSD: channels.c,v 1.301 2010/01/11 01:39:46 dtucker Exp $ */
/* $OpenBSD: channels.c,v 1.302 2010/01/26 01:28:35 djm Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@ -239,7 +239,6 @@ channel_register_fds(Channel *c, int rfd, int wfd, int efd,
c->rfd = rfd;
c->wfd = wfd;
c->sock = (rfd == wfd) ? rfd : -1;
c->ctl_fd = -1; /* XXX: set elsewhere */
c->efd = efd;
c->extended_usage = extusage;
@ -328,6 +327,9 @@ channel_new(char *ctype, int type, int rfd, int wfd, int efd,
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);
@ -370,11 +372,10 @@ channel_close_fd(int *fdp)
static void
channel_close_fds(Channel *c)
{
debug3("channel %d: close_fds r %d w %d e %d c %d",
c->self, c->rfd, c->wfd, c->efd, c->ctl_fd);
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->ctl_fd);
channel_close_fd(&c->rfd);
channel_close_fd(&c->wfd);
channel_close_fd(&c->efd);
@ -400,8 +401,6 @@ channel_free(Channel *c)
if (c->sock != -1)
shutdown(c->sock, SHUT_RDWR);
if (c->ctl_fd != -1)
shutdown(c->ctl_fd, SHUT_RDWR);
channel_close_fds(c);
buffer_free(&c->input);
buffer_free(&c->output);
@ -523,6 +522,7 @@ channel_still_open(void)
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:
@ -536,6 +536,7 @@ channel_still_open(void)
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:
@ -567,6 +568,8 @@ channel_find_open(void)
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:
@ -617,6 +620,8 @@ channel_open_message(void)
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:
@ -627,12 +632,12 @@ channel_open_message(void)
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 cfd %d)\r\n",
" #%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_fd);
c->rfd, c->wfd, c->ctl_chan);
buffer_append(&buffer, buf, strlen(buf));
continue;
default:
@ -839,9 +844,6 @@ channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
FD_SET(c->efd, readset);
}
/* XXX: What about efd? races? */
if (compat20 && c->ctl_fd != -1 &&
c->istate == CHAN_INPUT_OPEN && c->ostate == CHAN_OUTPUT_OPEN)
FD_SET(c->ctl_fd, readset);
}
/* ARGSUSED */
@ -986,6 +988,28 @@ channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
}
}
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
@ -1218,19 +1242,14 @@ channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
}
Channel *
channel_connect_stdio_fwd(const char *host_to_connect, u_short port_to_connect)
channel_connect_stdio_fwd(const char *host_to_connect, u_short port_to_connect,
int in, int out)
{
Channel *c;
int in, out;
debug("channel_connect_stdio_fwd %s:%d", host_to_connect,
port_to_connect);
in = dup(STDIN_FILENO);
out = dup(STDOUT_FILENO);
if (in < 0 || out < 0)
fatal("channel_connect_stdio_fwd: dup() in/out failed");
c = channel_new("stdio-forward", SSH_CHANNEL_OPENING, in, out,
-1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
0, "stdio-forward", /*nonblock*/0);
@ -1749,36 +1768,6 @@ channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
return 1;
}
/* ARGSUSED */
static int
channel_handle_ctl(Channel *c, fd_set *readset, fd_set *writeset)
{
char buf[16];
int len;
/* Monitor control fd to detect if the slave client exits */
if (c->ctl_fd != -1 && FD_ISSET(c->ctl_fd, readset)) {
len = read(c->ctl_fd, buf, sizeof(buf));
if (len < 0 &&
(errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK))
return 1;
if (len <= 0) {
debug2("channel %d: ctl read<=0", c->self);
if (c->type != SSH_CHANNEL_OPEN) {
debug2("channel %d: not open", c->self);
chan_mark_dead(c);
return -1;
} else {
chan_read_failed(c);
chan_write_failed(c);
}
return -1;
} else
fatal("%s: unexpected data on ctl fd", __func__);
}
return 1;
}
static int
channel_check_window(Channel *c)
{
@ -1809,10 +1798,131 @@ channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
if (!compat20)
return;
channel_handle_efd(c, readset, writeset);
channel_handle_ctl(c, readset, writeset);
channel_check_window(c);
}
static u_int
read_mux(Channel *c, u_int need)
{
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);
}
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)
@ -1841,6 +1951,8 @@ channel_handler_init_20(void)
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;
channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
@ -1849,6 +1961,8 @@ channel_handler_init_20(void)
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;
}
static void

18
channels.h
View File

@ -1,4 +1,4 @@
/* $OpenBSD: channels.h,v 1.102 2010/01/11 01:39:46 dtucker Exp $ */
/* $OpenBSD: channels.h,v 1.103 2010/01/26 01:28:35 djm Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
@ -53,7 +53,9 @@
#define SSH_CHANNEL_CONNECTING 12
#define SSH_CHANNEL_DYNAMIC 13
#define SSH_CHANNEL_ZOMBIE 14 /* Almost dead. */
#define SSH_CHANNEL_MAX_TYPE 15
#define SSH_CHANNEL_MUX_LISTENER 15 /* Listener for mux conn. */
#define SSH_CHANNEL_MUX_CLIENT 16 /* Conn. to mux slave */
#define SSH_CHANNEL_MAX_TYPE 17
struct Channel;
typedef struct Channel Channel;
@ -81,6 +83,9 @@ struct channel_connect {
struct addrinfo *ai, *aitop;
};
/* Callbacks for mux channels back into client-specific code */
typedef int mux_callback_fn(struct Channel *);
struct Channel {
int type; /* channel type/state */
int self; /* my own channel identifier */
@ -92,7 +97,7 @@ struct Channel {
int wfd; /* write fd */
int efd; /* extended fd */
int sock; /* sock fd */
int ctl_fd; /* control fd (client sharing) */
int ctl_chan; /* control channel (multiplexed connections) */
int isatty; /* rfd is a tty */
int wfd_isatty; /* wfd is a tty */
int client_tty; /* (client) TTY has been requested */
@ -142,6 +147,10 @@ struct Channel {
/* non-blocking connect */
struct channel_connect connect_ctx;
/* multiplexing protocol hook, called for each packet received */
mux_callback_fn *mux_rcb;
void *mux_ctx;
};
#define CHAN_EXTENDED_IGNORE 0
@ -172,6 +181,7 @@ struct Channel {
#define CHAN_CLOSE_RCVD 0x02
#define CHAN_EOF_SENT 0x04
#define CHAN_EOF_RCVD 0x08
#define CHAN_LOCAL 0x10
#define CHAN_RBUF 16*1024
@ -243,7 +253,7 @@ void channel_clear_adm_permitted_opens(void);
void channel_print_adm_permitted_opens(void);
int channel_input_port_forward_request(int, int);
Channel *channel_connect_to(const char *, u_short, char *, char *);
Channel *channel_connect_stdio_fwd(const char*, u_short);
Channel *channel_connect_stdio_fwd(const char*, u_short, int, int);
Channel *channel_connect_by_listen_address(u_short, char *, char *);
int channel_request_remote_forwarding(const char *, u_short,
const char *, u_short);

35
clientloop.c
View File

@ -1,4 +1,4 @@
/* $OpenBSD: clientloop.c,v 1.216 2010/01/09 05:04:24 djm Exp $ */
/* $OpenBSD: clientloop.c,v 1.217 2010/01/26 01:28:35 djm Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@ -121,7 +121,7 @@ extern int stdin_null_flag;
extern int no_shell_flag;
/* Control socket */
extern int muxserver_sock;
extern int muxserver_sock; /* XXX use mux_client_cleanup() instead */
/*
* Name of the host we are connecting to. This is the name given on the
@ -146,7 +146,7 @@ static volatile sig_atomic_t received_signal = 0;
static int in_non_blocking_mode = 0;
/* Common data for the client loop code. */
static volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
static int escape_char1; /* Escape character. (proto1 only) */
static int escape_pending1; /* Last character was an escape (proto1 only) */
static int last_was_cr; /* Last character was a newline. */
@ -564,9 +564,6 @@ client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
if (packet_have_data_to_write())
FD_SET(connection_out, *writesetp);
if (muxserver_sock != -1)
FD_SET(muxserver_sock, *readsetp);
/*
* Wait for something to happen. This will suspend the process until
* some selected descriptor can be read, written, or has some other
@ -695,7 +692,7 @@ client_status_confirm(int type, Channel *c, void *ctx)
/* XXX supress on mux _client_ quietmode */
tochan = options.log_level >= SYSLOG_LEVEL_ERROR &&
c->ctl_fd != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
if (type == SSH2_MSG_CHANNEL_SUCCESS) {
debug2("%s request accepted on channel %d",
@ -839,6 +836,7 @@ process_cmdline(void)
while (isspace(*++s))
;
/* XXX update list of forwards in options */
if (delete) {
cancel_port = 0;
cancel_host = hpdelim(&s); /* may be NULL */
@ -936,7 +934,7 @@ process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
escape_char);
buffer_append(berr, string, strlen(string));
if (c && c->ctl_fd != -1) {
if (c && c->ctl_chan != -1) {
chan_read_failed(c);
chan_write_failed(c);
return 0;
@ -946,7 +944,7 @@ process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
case 'Z' - 64:
/* XXX support this for mux clients */
if (c && c->ctl_fd != -1) {
if (c && c->ctl_chan != -1) {
noescape:
snprintf(string, sizeof string,
"%c%c escape not available to "
@ -991,7 +989,7 @@ process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
continue;
case '&':
if (c && c->ctl_fd != -1)
if (c && c->ctl_chan != -1)
goto noescape;
/*
* Detach the program (continue to serve
@ -1042,7 +1040,7 @@ process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
continue;
case '?':
if (c && c->ctl_fd != -1) {
if (c && c->ctl_chan != -1) {
snprintf(string, sizeof string,
"%c?\r\n\
Supported escape sequences:\r\n\
@ -1091,7 +1089,7 @@ Supported escape sequences:\r\n\
continue;
case 'C':
if (c && c->ctl_fd != -1)
if (c && c->ctl_chan != -1)
goto noescape;
process_cmdline();
continue;
@ -1327,8 +1325,6 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
connection_in = packet_get_connection_in();
connection_out = packet_get_connection_out();
max_fd = MAX(connection_in, connection_out);
if (muxserver_sock != -1)
max_fd = MAX(max_fd, muxserver_sock);
if (!compat20) {
/* enable nonblocking unless tty */
@ -1446,12 +1442,6 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
/* Buffer input from the connection. */
client_process_net_input(readset);
/* Accept control connections. */
if (muxserver_sock != -1 &&FD_ISSET(muxserver_sock, readset)) {
if (muxserver_accept_control())
quit_pending = 1;
}
if (quit_pending)
break;
@ -1859,9 +1849,8 @@ client_input_channel_req(int type, u_int32_t seq, void *ctxt)
chan_rcvd_eow(c);
} else if (strcmp(rtype, "exit-status") == 0) {
exitval = packet_get_int();
if (c->ctl_fd != -1) {
/* Dispatch to mux client */
atomicio(vwrite, c->ctl_fd, &exitval, sizeof(exitval));
if (c->ctl_chan != -1) {
mux_exit_message(c, exitval);
success = 1;
} else if (id == session_ident) {
/* Record exit value of local session */

12
clientloop.h
View File

@ -1,4 +1,4 @@
/* $OpenBSD: clientloop.h,v 1.22 2008/06/12 15:19:17 djm Exp $ */
/* $OpenBSD: clientloop.h,v 1.23 2010/01/26 01:28:35 djm Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
@ -56,18 +56,14 @@ typedef void global_confirm_cb(int, u_int32_t seq, void *);
void client_register_global_confirm(global_confirm_cb *, void *);
/* Multiplexing protocol version */
#define SSHMUX_VER 2
#define SSHMUX_VER 4
/* Multiplexing control protocol flags */
#define SSHMUX_COMMAND_OPEN 1 /* Open new connection */
#define SSHMUX_COMMAND_ALIVE_CHECK 2 /* Check master is alive */
#define SSHMUX_COMMAND_TERMINATE 3 /* Ask master to exit */
#define SSHMUX_FLAG_TTY (1) /* Request tty on open */
#define SSHMUX_FLAG_SUBSYS (1<<1) /* Subsystem request on open */
#define SSHMUX_FLAG_X11_FWD (1<<2) /* Request X11 forwarding */
#define SSHMUX_FLAG_AGENT_FWD (1<<3) /* Request agent forwarding */
#define SSHMUX_COMMAND_STDIO_FWD 4 /* Open stdio fwd (ssh -W) */
void muxserver_listen(void);
int muxserver_accept_control(void);
void muxclient(const char *);
void mux_exit_message(Channel *, int);

1912
mux.c
View File

File diff suppressed because it is too large Load Diff

21
nchan.c
View File

@ -1,4 +1,4 @@
/* $OpenBSD: nchan.c,v 1.62 2008/11/07 18:50:18 stevesk Exp $ */
/* $OpenBSD: nchan.c,v 1.63 2010/01/26 01:28:35 djm Exp $ */
/*
* Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
*
@ -161,7 +161,7 @@ chan_ibuf_empty(Channel *c)
switch (c->istate) {
case CHAN_INPUT_WAIT_DRAIN:
if (compat20) {
if (!(c->flags & CHAN_CLOSE_SENT))
if (!(c->flags & (CHAN_CLOSE_SENT|CHAN_LOCAL)))
chan_send_eof2(c);
chan_set_istate(c, CHAN_INPUT_CLOSED);
} else {
@ -278,9 +278,12 @@ static void
chan_rcvd_close2(Channel *c)
{
debug2("channel %d: rcvd close", c->self);
if (c->flags & CHAN_CLOSE_RCVD)
error("channel %d: protocol error: close rcvd twice", c->self);
c->flags |= CHAN_CLOSE_RCVD;
if (!(c->flags & CHAN_LOCAL)) {
if (c->flags & CHAN_CLOSE_RCVD)
error("channel %d: protocol error: close rcvd twice",
c->self);
c->flags |= CHAN_CLOSE_RCVD;
}
if (c->type == SSH_CHANNEL_LARVAL) {
/* tear down larval channels immediately */
chan_set_ostate(c, CHAN_OUTPUT_CLOSED);
@ -302,11 +305,13 @@ chan_rcvd_close2(Channel *c)
chan_set_istate(c, CHAN_INPUT_CLOSED);
break;
case CHAN_INPUT_WAIT_DRAIN:
chan_send_eof2(c);
if (!(c->flags & CHAN_LOCAL))
chan_send_eof2(c);
chan_set_istate(c, CHAN_INPUT_CLOSED);
break;
}
}
void
chan_rcvd_eow(Channel *c)
{
@ -454,6 +459,10 @@ chan_is_dead(Channel *c, int do_send)
c->self, c->efd, buffer_len(&c->extended));
return 0;
}
if (c->flags & CHAN_LOCAL) {
debug2("channel %d: is dead (local)", c->self);
return 1;
}
if (!(c->flags & CHAN_CLOSE_SENT)) {
if (do_send) {
chan_send_close2(c);

22
ssh.c
View File

@ -1,4 +1,4 @@
/* $OpenBSD: ssh.c,v 1.331 2010/01/11 01:39:46 dtucker Exp $ */
/* $OpenBSD: ssh.c,v 1.332 2010/01/26 01:28:35 djm Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@ -319,6 +319,11 @@ main(int ac, char **av)
options.gateway_ports = 1;
break;
case 'O':
if (stdio_forward_host != NULL)
fatal("Cannot specify multiplexing "
"command with -W");
else if (muxclient_command != 0)
fatal("Multiplexing command already specified");
if (strcmp(optarg, "check") == 0)
muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
else if (strcmp(optarg, "exit") == 0)
@ -395,6 +400,10 @@ main(int ac, char **av)
}
break;
case 'W':
if (stdio_forward_host != NULL)
fatal("stdio forward already specified");
if (muxclient_command != 0)
fatal("Cannot specify stdio forward with -O");
if (parse_forward(&fwd, optarg, 1, 0)) {
stdio_forward_host = fwd.listen_host;
stdio_forward_port = fwd.listen_port;
@ -902,11 +911,18 @@ static int
client_setup_stdio_fwd(const char *host_to_connect, u_short port_to_connect)
{
Channel *c;
int in, out;
debug3("client_setup_stdio_fwd %s:%d", host_to_connect,
port_to_connect);
if ((c = channel_connect_stdio_fwd(host_to_connect, port_to_connect))
== NULL)
in = dup(STDIN_FILENO);
out = dup(STDOUT_FILENO);
if (in < 0 || out < 0)
fatal("channel_connect_stdio_fwd: dup() in/out failed");
if ((c = channel_connect_stdio_fwd(host_to_connect, port_to_connect,
in, out)) == NULL)
return 0;
channel_register_cleanup(c->self, client_cleanup_stdio_fwd, 0);
return 1;