- djm@cvs.openbsd.org 2004/06/13 15:03:02
[channels.c channels.h clientloop.c clientloop.h includes.h readconf.c]
[readconf.h scp.1 sftp.1 ssh.1 ssh.c ssh_config.5]
implement session multiplexing in the client (the server has supported
this since 2.0); ok markus@
diff --git a/clientloop.c b/clientloop.c
index 31e6041..6401588 100644
--- a/clientloop.c
+++ b/clientloop.c
@@ -59,7 +59,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: clientloop.c,v 1.122 2004/05/22 06:32:12 djm Exp $");
+RCSID("$OpenBSD: clientloop.c,v 1.123 2004/06/13 15:03:02 djm Exp $");
#include "ssh.h"
#include "ssh1.h"
@@ -81,6 +81,9 @@
#include "atomicio.h"
#include "sshpty.h"
#include "misc.h"
+#include "monitor_fdpass.h"
+#include "match.h"
+#include "msg.h"
/* import options */
extern Options options;
@@ -91,6 +94,9 @@
/* Flag indicating that no shell has been requested */
extern int no_shell_flag;
+/* Control socket */
+extern int control_fd;
+
/*
* Name of the host we are connecting to. This is the name given on the
* command line, or the HostName specified for the user-supplied name in a
@@ -131,9 +137,19 @@
static void client_init_dispatch(void);
int session_ident = -1;
+struct confirm_ctx {
+ int want_tty;
+ int want_subsys;
+ Buffer cmd;
+ char *term;
+ struct termios tio;
+};
+
/*XXX*/
extern Kex *xxx_kex;
+void ssh_process_session2_setup(int, int, int, Buffer *);
+
/* Restores stdin to blocking mode. */
static void
@@ -291,19 +307,13 @@
/** XXX race */
received_window_change_signal = 0;
- if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
- return;
-
debug2("client_check_window_change: changed");
if (compat20) {
- channel_request_start(session_ident, "window-change", 0);
- packet_put_int(ws.ws_col);
- packet_put_int(ws.ws_row);
- packet_put_int(ws.ws_xpixel);
- packet_put_int(ws.ws_ypixel);
- packet_send();
+ channel_send_window_changes();
} else {
+ if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
+ return;
packet_start(SSH_CMSG_WINDOW_SIZE);
packet_put_int(ws.ws_row);
packet_put_int(ws.ws_col);
@@ -335,7 +345,6 @@
* Waits until the client can do something (some data becomes available on
* one of the file descriptors).
*/
-
static void
client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
int *maxfdp, int *nallocp, int rekeying)
@@ -381,6 +390,9 @@
if (packet_have_data_to_write())
FD_SET(connection_out, *writesetp);
+ if (control_fd != -1)
+ FD_SET(control_fd, *readsetp);
+
/*
* Wait for something to happen. This will suspend the process until
* some selected descriptor can be read, written, or has some other
@@ -500,6 +512,176 @@
}
static void
+client_subsystem_reply(int type, u_int32_t seq, void *ctxt)
+{
+ int id;
+ Channel *c;
+
+ id = packet_get_int();
+ packet_check_eom();
+
+ if ((c = channel_lookup(id)) == NULL) {
+ error("%s: no channel for id %d", __func__, id);
+ return;
+ }
+
+ if (type == SSH2_MSG_CHANNEL_SUCCESS)
+ debug2("Request suceeded on channel %d", id);
+ else if (type == SSH2_MSG_CHANNEL_FAILURE) {
+ error("Request failed on channel %d", id);
+ channel_free(c);
+ }
+}
+
+static void
+client_extra_session2_setup(int id, void *arg)
+{
+ struct confirm_ctx *cctx = arg;
+ Channel *c;
+
+ if (cctx == NULL)
+ fatal("%s: cctx == NULL", __func__);
+ if ((c = channel_lookup(id)) == NULL)
+ fatal("%s: no channel for id %d", __func__, id);
+
+ client_session2_setup(id, cctx->want_tty, cctx->want_subsys,
+ cctx->term, &cctx->tio, c->rfd, &cctx->cmd,
+ client_subsystem_reply);
+
+ c->confirm_ctx = NULL;
+ buffer_free(&cctx->cmd);
+ free(cctx->term);
+ free(cctx);
+}
+
+static void
+client_process_control(fd_set * readset)
+{
+ Buffer m;
+ Channel *c;
+ int client_fd, new_fd[3], ver;
+ socklen_t addrlen;
+ struct sockaddr_storage addr;
+ struct confirm_ctx *cctx;
+ char *cmd;
+ u_int len;
+ uid_t euid;
+ gid_t egid;
+
+ /*
+ * Accept connection on control socket
+ */
+ if (control_fd == -1 || !FD_ISSET(control_fd, readset))
+ return;
+
+ memset(&addr, 0, sizeof(addr));
+ addrlen = sizeof(addr);
+ if ((client_fd = accept(control_fd,
+ (struct sockaddr*)&addr, &addrlen)) == -1) {
+ error("%s accept: %s", __func__, strerror(errno));
+ return;
+ }
+
+ if (getpeereid(client_fd, &euid, &egid) < 0) {
+ error("%s getpeereid failed: %s", __func__, strerror(errno));
+ close(client_fd);
+ return;
+ }
+ if ((euid != 0) && (getuid() != euid)) {
+ error("control mode uid mismatch: peer euid %u != uid %u",
+ (u_int) euid, (u_int) getuid());
+ close(client_fd);
+ return;
+ }
+ /* XXX: implement use of ssh-askpass to confirm additional channels */
+
+ unset_nonblock(client_fd);
+
+ buffer_init(&m);
+
+ buffer_put_int(&m, getpid());
+ if (ssh_msg_send(client_fd, /* version */0, &m) == -1) {
+ error("%s: client msg_send failed", __func__);
+ close(client_fd);
+ return;
+ }
+ buffer_clear(&m);
+
+ if (ssh_msg_recv(client_fd, &m) == -1) {
+ error("%s: client msg_recv failed", __func__);
+ close(client_fd);
+ return;
+ }
+
+ if ((ver = buffer_get_char(&m)) != 0) {
+ error("%s: wrong client version %d", __func__, ver);
+ buffer_free(&m);
+ close(client_fd);
+ return;
+ }
+
+ cctx = xmalloc(sizeof(*cctx));
+ memset(cctx, 0, sizeof(*cctx));
+
+ cctx->want_tty = buffer_get_int(&m);
+ cctx->want_subsys = buffer_get_int(&m);
+ cctx->term = buffer_get_string(&m, &len);
+
+ cmd = buffer_get_string(&m, &len);
+ buffer_init(&cctx->cmd);
+ buffer_append(&cctx->cmd, cmd, strlen(cmd));
+
+ debug2("%s: accepted tty %d, subsys %d, cmd %s", __func__,
+ cctx->want_tty, cctx->want_subsys, cmd);
+
+ /* Gather fds from client */
+ new_fd[0] = mm_receive_fd(client_fd);
+ new_fd[1] = mm_receive_fd(client_fd);
+ new_fd[2] = mm_receive_fd(client_fd);
+
+ debug2("%s: got fds stdin %d, stdout %d, stderr %d", __func__,
+ new_fd[0], new_fd[1], new_fd[2]);
+
+ /* Try to pick up ttymodes from client before it goes raw */
+ if (cctx->want_tty && tcgetattr(new_fd[0], &cctx->tio) == -1)
+ error("%s: tcgetattr: %s", __func__, strerror(errno));
+
+ buffer_clear(&m);
+ if (ssh_msg_send(client_fd, /* version */0, &m) == -1) {
+ error("%s: client msg_send failed", __func__);
+ close(client_fd);
+ close(new_fd[0]);
+ close(new_fd[1]);
+ close(new_fd[2]);
+ return;
+ }
+ buffer_free(&m);
+
+ /* enable nonblocking unless tty */
+ if (!isatty(new_fd[0]))
+ set_nonblock(new_fd[0]);
+ if (!isatty(new_fd[1]))
+ set_nonblock(new_fd[1]);
+ if (!isatty(new_fd[2]))
+ set_nonblock(new_fd[2]);
+
+ set_nonblock(client_fd);
+
+ c = channel_new("session", SSH_CHANNEL_OPENING,
+ new_fd[0], new_fd[1], new_fd[2],
+ CHAN_SES_WINDOW_DEFAULT, CHAN_SES_PACKET_DEFAULT,
+ CHAN_EXTENDED_WRITE, "client-session", /*nonblock*/0);
+
+ /* XXX */
+ c->ctl_fd = client_fd;
+
+ debug3("%s: channel_new: %d", __func__, c->self);
+
+ channel_send_open(c->self);
+ channel_register_confirm(c->self, client_extra_session2_setup, cctx);
+}
+
+static void
process_cmdline(void)
{
void (*handler)(int);
@@ -901,9 +1083,6 @@
static void
client_channel_closed(int id, void *arg)
{
- if (id != session_ident)
- error("client_channel_closed: id %d != session_ident %d",
- id, session_ident);
channel_cancel_cleanup(id);
session_closed = 1;
leave_raw_mode();
@@ -937,6 +1116,8 @@
connection_in = packet_get_connection_in();
connection_out = packet_get_connection_out();
max_fd = MAX(connection_in, connection_out);
+ if (control_fd != -1)
+ max_fd = MAX(max_fd, control_fd);
if (!compat20) {
/* enable nonblocking unless tty */
@@ -1054,6 +1235,9 @@
/* Buffer input from the connection. */
client_process_net_input(readset);
+ /* Accept control connections. */
+ client_process_control(readset);
+
if (quit_pending)
break;
@@ -1385,7 +1569,7 @@
client_input_channel_req(int type, u_int32_t seq, void *ctxt)
{
Channel *c = NULL;
- int id, reply, success = 0;
+ int exitval, id, reply, success = 0;
char *rtype;
id = packet_get_int();
@@ -1395,18 +1579,21 @@
debug("client_input_channel_req: channel %d rtype %s reply %d",
id, rtype, reply);
- if (session_ident == -1) {
- error("client_input_channel_req: no channel %d", session_ident);
- } else if (id != session_ident) {
- error("client_input_channel_req: channel %d: wrong channel: %d",
- session_ident, id);
- }
c = channel_lookup(id);
if (c == NULL) {
error("client_input_channel_req: channel %d: unknown channel", id);
} else if (strcmp(rtype, "exit-status") == 0) {
- success = 1;
- exit_status = packet_get_int();
+ exitval = packet_get_int();
+ if (id == session_ident) {
+ success = 1;
+ exit_status = exitval;
+ } else if (c->ctl_fd == -1) {
+ error("client_input_channel_req: unexpected channel %d",
+ session_ident);
+ } else {
+ atomicio(vwrite, c->ctl_fd, &exitval, sizeof(exitval));
+ success = 1;
+ }
packet_check_eom();
}
if (reply) {
@@ -1437,6 +1624,98 @@
xfree(rtype);
}
+void
+client_session2_setup(int id, int want_tty, int want_subsystem,
+ const char *term, struct termios *tiop, int in_fd, Buffer *cmd,
+ dispatch_fn *subsys_repl)
+{
+ int len;
+
+ debug2("%s: id %d", __func__, id);
+
+ if (want_tty) {
+ struct winsize ws;
+ struct termios tio;
+
+ /* Store window size in the packet. */
+ if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
+ memset(&ws, 0, sizeof(ws));
+
+ channel_request_start(id, "pty-req", 0);
+ packet_put_cstring(term != NULL ? term : "");
+ packet_put_int(ws.ws_col);
+ packet_put_int(ws.ws_row);
+ packet_put_int(ws.ws_xpixel);
+ packet_put_int(ws.ws_ypixel);
+ tio = get_saved_tio();
+ tty_make_modes(-1, tiop != NULL ? tiop : &tio);
+ packet_send();
+ /* XXX wait for reply */
+ }
+
+ /* Transfer any environment variables from client to server */
+ if (options.num_send_env != 0) {
+ int i, j, matched;
+ extern char **environ;
+ char *name, *val;
+
+ debug("Sending environment.");
+ for (i = 0; environ && environ[i] != NULL; i++) {
+ /* Split */
+ name = xstrdup(environ[i]);
+ if ((val = strchr(name, '=')) == NULL) {
+ free(name);
+ continue;
+ }
+ *val++ = '\0';
+
+ matched = 0;
+ for (j = 0; j < options.num_send_env; j++) {
+ if (match_pattern(name, options.send_env[j])) {
+ matched = 1;
+ break;
+ }
+ }
+ if (!matched) {
+ debug3("Ignored env %s", name);
+ free(name);
+ continue;
+ }
+
+ debug("Sending env %s = %s", name, val);
+ channel_request_start(id, "env", 0);
+ packet_put_cstring(name);
+ packet_put_cstring(val);
+ packet_send();
+ free(name);
+ }
+ }
+
+ len = buffer_len(cmd);
+ if (len > 0) {
+ if (len > 900)
+ len = 900;
+ if (want_subsystem) {
+ debug("Sending subsystem: %.*s", len, (u_char*)buffer_ptr(cmd));
+ channel_request_start(id, "subsystem", subsys_repl != NULL);
+ if (subsys_repl != NULL) {
+ /* register callback for reply */
+ /* XXX we assume that client_loop has already been called */
+ dispatch_set(SSH2_MSG_CHANNEL_FAILURE, subsys_repl);
+ dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, subsys_repl);
+ }
+ } else {
+ debug("Sending command: %.*s", len, (u_char*)buffer_ptr(cmd));
+ channel_request_start(id, "exec", 0);
+ }
+ packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
+ packet_send();
+ } else {
+ channel_request_start(id, "shell", 0);
+ packet_send();
+ }
+}
+
static void
client_init_dispatch_20(void)
{
@@ -1503,5 +1782,7 @@
{
leave_raw_mode();
leave_non_blocking();
+ if (options.control_path != NULL && control_fd != -1)
+ unlink(options.control_path);
_exit(i);
}