- djm@cvs.openbsd.org 2008/05/09 14:18:44
[clientloop.c clientloop.h ssh.c mux.c]
tidy up session multiplexing code, moving it into its own file and
making the function names more consistent - making ssh.c and
clientloop.c a fair bit more readable.
ok markus@
diff --git a/ChangeLog b/ChangeLog
index 9e68314..90ee86a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -111,6 +111,12 @@
was to try the first address and give up.
Reported by stig AT venaas.com in bz#343
great feedback and ok markus@
+ - djm@cvs.openbsd.org 2008/05/09 14:18:44
+ [clientloop.c clientloop.h ssh.c mux.c]
+ tidy up session multiplexing code, moving it into its own file and
+ making the function names more consistent - making ssh.c and
+ clientloop.c a fair bit more readable.
+ ok markus@
20080403
- (djm) [openbsd-compat/bsd-poll.c] Include stdlib.h to avoid compile-
@@ -3971,4 +3977,4 @@
OpenServer 6 and add osr5bigcrypt support so when someone migrates
passwords between UnixWare and OpenServer they will still work. OK dtucker@
-$Id: ChangeLog,v 1.4925 2008/05/19 05:37:09 djm Exp $
+$Id: ChangeLog,v 1.4926 2008/05/19 06:00:08 djm Exp $
diff --git a/Makefile.in b/Makefile.in
index 6b488fe..b57b9b7 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -1,4 +1,4 @@
-# $Id: Makefile.in,v 1.289 2008/03/13 01:41:31 djm Exp $
+# $Id: Makefile.in,v 1.290 2008/05/19 06:00:08 djm Exp $
# uncomment if you run a non bourne compatable shell. Ie. csh
#SHELL = @SH@
@@ -74,7 +74,7 @@
entropy.o scard-opensc.o gss-genr.o umac.o
SSHOBJS= ssh.o readconf.o clientloop.o sshtty.o \
- sshconnect.o sshconnect1.o sshconnect2.o
+ sshconnect.o sshconnect1.o sshconnect2.o mux.o
SSHDOBJS=sshd.o auth-rhosts.o auth-passwd.o auth-rsa.o auth-rh-rsa.o \
sshpty.o sshlogin.o servconf.o serverloop.o \
diff --git a/clientloop.c b/clientloop.c
index 7bd1af6..c87aa5a 100644
--- a/clientloop.c
+++ b/clientloop.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: clientloop.c,v 1.191 2008/05/09 04:55:56 djm Exp $ */
+/* $OpenBSD: clientloop.c,v 1.192 2008/05/09 14:18:44 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 no_shell_flag;
/* Control socket */
-extern int control_fd;
+extern int muxserver_sock;
/*
* Name of the host we are connecting to. This is the name given on the
@@ -162,17 +162,6 @@
static void client_init_dispatch(void);
int session_ident = -1;
-struct confirm_ctx {
- int want_tty;
- int want_subsys;
- int want_x_fwd;
- int want_agent_fwd;
- Buffer cmd;
- char *term;
- struct termios tio;
- char **env;
-};
-
struct channel_reply_ctx {
const char *request_type;
int id, do_close;
@@ -538,8 +527,8 @@
if (packet_have_data_to_write())
FD_SET(connection_out, *writesetp);
- if (control_fd != -1)
- FD_SET(control_fd, *readsetp);
+ if (muxserver_sock != -1)
+ FD_SET(muxserver_sock, *readsetp);
/*
* Wait for something to happen. This will suspend the process until
@@ -707,284 +696,6 @@
}
static void
-client_extra_session2_setup(int id, void *arg)
-{
- struct confirm_ctx *cctx = arg;
- const char *display;
- Channel *c;
- int i;
-
- if (cctx == NULL)
- fatal("%s: cctx == NULL", __func__);
- if ((c = channel_lookup(id)) == NULL)
- fatal("%s: no channel for id %d", __func__, id);
-
- display = getenv("DISPLAY");
- if (cctx->want_x_fwd && options.forward_x11 && display != NULL) {
- char *proto, *data;
- /* Get reasonable local authentication information. */
- client_x11_get_proto(display, options.xauth_location,
- options.forward_x11_trusted, &proto, &data);
- /* Request forwarding with authentication spoofing. */
- debug("Requesting X11 forwarding with authentication spoofing.");
- x11_request_forwarding_with_spoofing(id, display, proto, data);
- /* XXX wait for reply */
- }
-
- if (cctx->want_agent_fwd && options.forward_agent) {
- debug("Requesting authentication agent forwarding.");
- channel_request_start(id, "auth-agent-req@openssh.com", 0);
- packet_send();
- }
-
- client_session2_setup(id, cctx->want_tty, cctx->want_subsys,
- cctx->term, &cctx->tio, c->rfd, &cctx->cmd, cctx->env);
-
- c->open_confirm_ctx = NULL;
- buffer_free(&cctx->cmd);
- xfree(cctx->term);
- if (cctx->env != NULL) {
- for (i = 0; cctx->env[i] != NULL; i++)
- xfree(cctx->env[i]);
- xfree(cctx->env);
- }
- xfree(cctx);
-}
-
-static void
-client_process_control(fd_set *readset)
-{
- Buffer m;
- Channel *c;
- int client_fd, new_fd[3], ver, allowed, window, packetmax;
- socklen_t addrlen;
- struct sockaddr_storage addr;
- struct confirm_ctx *cctx;
- char *cmd;
- u_int i, j, len, env_len, command, flags;
- 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;
- }
-
- unset_nonblock(client_fd);
-
- /* Read command */
- buffer_init(&m);
- if (ssh_msg_recv(client_fd, &m) == -1) {
- error("%s: client msg_recv failed", __func__);
- close(client_fd);
- buffer_free(&m);
- return;
- }
- if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
- error("%s: wrong client version %d", __func__, ver);
- buffer_free(&m);
- close(client_fd);
- return;
- }
-
- allowed = 1;
- command = buffer_get_int(&m);
- flags = buffer_get_int(&m);
-
- buffer_clear(&m);
-
- switch (command) {
- case SSHMUX_COMMAND_OPEN:
- if (options.control_master == SSHCTL_MASTER_ASK ||
- options.control_master == SSHCTL_MASTER_AUTO_ASK)
- allowed = ask_permission("Allow shared connection "
- "to %s? ", host);
- /* continue below */
- break;
- case SSHMUX_COMMAND_TERMINATE:
- if (options.control_master == SSHCTL_MASTER_ASK ||
- options.control_master == SSHCTL_MASTER_AUTO_ASK)
- allowed = ask_permission("Terminate shared connection "
- "to %s? ", host);
- if (allowed)
- quit_pending = 1;
- /* FALLTHROUGH */
- case SSHMUX_COMMAND_ALIVE_CHECK:
- /* Reply for SSHMUX_COMMAND_TERMINATE and ALIVE_CHECK */
- buffer_clear(&m);
- buffer_put_int(&m, allowed);
- buffer_put_int(&m, getpid());
- if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
- error("%s: client msg_send failed", __func__);
- close(client_fd);
- buffer_free(&m);
- return;
- }
- buffer_free(&m);
- close(client_fd);
- return;
- default:
- error("Unsupported command %d", command);
- buffer_free(&m);
- close(client_fd);
- return;
- }
-
- /* Reply for SSHMUX_COMMAND_OPEN */
- buffer_clear(&m);
- buffer_put_int(&m, allowed);
- buffer_put_int(&m, getpid());
- if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
- error("%s: client msg_send failed", __func__);
- close(client_fd);
- buffer_free(&m);
- return;
- }
-
- if (!allowed) {
- error("Refused control connection");
- close(client_fd);
- buffer_free(&m);
- return;
- }
-
- buffer_clear(&m);
- if (ssh_msg_recv(client_fd, &m) == -1) {
- error("%s: client msg_recv failed", __func__);
- close(client_fd);
- buffer_free(&m);
- return;
- }
- if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
- error("%s: wrong client version %d", __func__, ver);
- buffer_free(&m);
- close(client_fd);
- return;
- }
-
- cctx = xcalloc(1, sizeof(*cctx));
- cctx->want_tty = (flags & SSHMUX_FLAG_TTY) != 0;
- cctx->want_subsys = (flags & SSHMUX_FLAG_SUBSYS) != 0;
- cctx->want_x_fwd = (flags & SSHMUX_FLAG_X11_FWD) != 0;
- cctx->want_agent_fwd = (flags & SSHMUX_FLAG_AGENT_FWD) != 0;
- cctx->term = buffer_get_string(&m, &len);
-
- cmd = buffer_get_string(&m, &len);
- buffer_init(&cctx->cmd);
- buffer_append(&cctx->cmd, cmd, strlen(cmd));
-
- env_len = buffer_get_int(&m);
- env_len = MIN(env_len, 4096);
- debug3("%s: receiving %d env vars", __func__, env_len);
- if (env_len != 0) {
- cctx->env = xcalloc(env_len + 1, sizeof(*cctx->env));
- for (i = 0; i < env_len; i++)
- cctx->env[i] = buffer_get_string(&m, &len);
- cctx->env[i] = NULL;
- }
-
- debug2("%s: accepted tty %d, subsys %d, cmd %s", __func__,
- cctx->want_tty, cctx->want_subsys, cmd);
- xfree(cmd);
-
- /* Gather fds from client */
- for(i = 0; i < 3; i++) {
- if ((new_fd[i] = mm_receive_fd(client_fd)) == -1) {
- error("%s: failed to receive fd %d from slave",
- __func__, i);
- for (j = 0; j < i; j++)
- close(new_fd[j]);
- for (j = 0; j < env_len; j++)
- xfree(cctx->env[j]);
- if (env_len > 0)
- xfree(cctx->env);
- xfree(cctx->term);
- buffer_free(&cctx->cmd);
- close(client_fd);
- xfree(cctx);
- return;
- }
- }
-
- 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));
-
- /* This roundtrip is just for synchronisation of ttymodes */
- buffer_clear(&m);
- if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
- error("%s: client msg_send failed", __func__);
- close(client_fd);
- close(new_fd[0]);
- close(new_fd[1]);
- close(new_fd[2]);
- buffer_free(&m);
- xfree(cctx->term);
- if (env_len != 0) {
- for (i = 0; i < env_len; i++)
- xfree(cctx->env[i]);
- xfree(cctx->env);
- }
- 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);
-
- window = CHAN_SES_WINDOW_DEFAULT;
- packetmax = CHAN_SES_PACKET_DEFAULT;
- if (cctx->want_tty) {
- window >>= 1;
- packetmax >>= 1;
- }
-
- c = channel_new("session", SSH_CHANNEL_OPENING,
- new_fd[0], new_fd[1], new_fd[2], window, packetmax,
- 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_open_confirm(c->self,
- client_extra_session2_setup, cctx);
-}
-
-static void
process_cmdline(void)
{
void (*handler)(int);
@@ -1448,8 +1159,8 @@
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 (muxserver_sock != -1)
+ max_fd = MAX(max_fd, muxserver_sock);
if (!compat20) {
/* enable nonblocking unless tty */
@@ -1569,7 +1280,10 @@
client_process_net_input(readset);
/* Accept control connections. */
- client_process_control(readset);
+ if (muxserver_sock != -1 &&FD_ISSET(muxserver_sock, readset)) {
+ if (muxserver_accept_control())
+ quit_pending = 1;
+ }
if (quit_pending)
break;
@@ -2157,7 +1871,7 @@
{
leave_raw_mode();
leave_non_blocking();
- if (options.control_path != NULL && control_fd != -1)
+ if (options.control_path != NULL && muxserver_sock != -1)
unlink(options.control_path);
_exit(i);
}
diff --git a/clientloop.h b/clientloop.h
index cb2d7c0..6f8e701 100644
--- a/clientloop.h
+++ b/clientloop.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: clientloop.h,v 1.18 2008/05/08 13:06:11 djm Exp $ */
+/* $OpenBSD: clientloop.h,v 1.19 2008/05/09 14:18:44 djm Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -58,3 +58,21 @@
#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 */
+
+/* Multiplexing routines */
+
+struct mux_session_confirm_ctx {
+ int want_tty;
+ int want_subsys;
+ int want_x_fwd;
+ int want_agent_fwd;
+ Buffer cmd;
+ char *term;
+ struct termios tio;
+ char **env;
+};
+
+/* mux.c */
+void muxserver_listen(void);
+int muxserver_accept_control(void);
+void muxclient(const char *);
diff --git a/mux.c b/mux.c
new file mode 100644
index 0000000..78ba631
--- /dev/null
+++ b/mux.c
@@ -0,0 +1,646 @@
+/* $OpenBSD: mux.c,v 1.1 2008/05/09 14:18:44 djm Exp $ */
+/*
+ * Copyright (c) 2002-2008 Damien Miller <djm@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* ssh session multiplexing support */
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdarg.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <util.h>
+#include <paths.h>
+
+#include "openbsd-compat/sys-queue.h"
+#include "xmalloc.h"
+#include "log.h"
+#include "ssh.h"
+#include "pathnames.h"
+#include "misc.h"
+#include "match.h"
+#include "buffer.h"
+#include "channels.h"
+#include "msg.h"
+#include "packet.h"
+#include "monitor_fdpass.h"
+#include "sshpty.h"
+#include "key.h"
+#include "readconf.h"
+#include "clientloop.h"
+
+/* from ssh.c */
+extern int tty_flag;
+extern Options options;
+extern int stdin_null_flag;
+extern char *host;
+int subsystem_flag;
+extern Buffer command;
+
+/* fd to control socket */
+int muxserver_sock = -1;
+
+/* Multiplexing control command */
+u_int muxclient_command = 0;
+
+/* Set when signalled. */
+static volatile sig_atomic_t muxclient_terminate = 0;
+
+/* PID of multiplex server */
+static u_int muxserver_pid = 0;
+
+
+/* ** Multiplexing master support */
+
+/* Prepare a mux master to listen on a Unix domain socket. */
+void
+muxserver_listen(void)
+{
+ struct sockaddr_un addr;
+ mode_t old_umask;
+ int addr_len;
+
+ if (options.control_path == NULL ||
+ options.control_master == SSHCTL_MASTER_NO)
+ return;
+
+ debug("setting up multiplex master socket");
+
+ memset(&addr, '\0', sizeof(addr));
+ addr.sun_family = AF_UNIX;
+ addr_len = offsetof(struct sockaddr_un, sun_path) +
+ strlen(options.control_path) + 1;
+
+ if (strlcpy(addr.sun_path, options.control_path,
+ sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
+ fatal("ControlPath too long");
+
+ if ((muxserver_sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
+ fatal("%s socket(): %s", __func__, strerror(errno));
+
+ old_umask = umask(0177);
+ if (bind(muxserver_sock, (struct sockaddr *)&addr, addr_len) == -1) {
+ muxserver_sock = -1;
+ if (errno == EINVAL || errno == EADDRINUSE)
+ fatal("ControlSocket %s already exists",
+ options.control_path);
+ else
+ fatal("%s bind(): %s", __func__, strerror(errno));
+ }
+ umask(old_umask);
+
+ if (listen(muxserver_sock, 64) == -1)
+ fatal("%s listen(): %s", __func__, strerror(errno));
+
+ set_nonblock(muxserver_sock);
+}
+
+/* Callback on open confirmation in mux master for a mux client session. */
+static void
+client_extra_session2_setup(int id, void *arg)
+{
+ struct mux_session_confirm_ctx *cctx = arg;
+ const char *display;
+ Channel *c;
+ int i;
+
+ if (cctx == NULL)
+ fatal("%s: cctx == NULL", __func__);
+ if ((c = channel_lookup(id)) == NULL)
+ fatal("%s: no channel for id %d", __func__, id);
+
+ display = getenv("DISPLAY");
+ if (cctx->want_x_fwd && options.forward_x11 && display != NULL) {
+ char *proto, *data;
+ /* Get reasonable local authentication information. */
+ client_x11_get_proto(display, options.xauth_location,
+ options.forward_x11_trusted, &proto, &data);
+ /* Request forwarding with authentication spoofing. */
+ debug("Requesting X11 forwarding with authentication spoofing.");
+ x11_request_forwarding_with_spoofing(id, display, proto, data);
+ /* XXX wait for reply */
+ }
+
+ if (cctx->want_agent_fwd && options.forward_agent) {
+ debug("Requesting authentication agent forwarding.");
+ channel_request_start(id, "auth-agent-req@openssh.com", 0);
+ packet_send();
+ }
+
+ client_session2_setup(id, cctx->want_tty, cctx->want_subsys,
+ cctx->term, &cctx->tio, c->rfd, &cctx->cmd, cctx->env);
+
+ c->open_confirm_ctx = NULL;
+ buffer_free(&cctx->cmd);
+ xfree(cctx->term);
+ if (cctx->env != NULL) {
+ for (i = 0; cctx->env[i] != NULL; i++)
+ xfree(cctx->env[i]);
+ xfree(cctx->env);
+ }
+ xfree(cctx);
+}
+
+/*
+ * Accept a connection on the mux master socket and process the
+ * client's request. Returns flag indicating whether mux master should
+ * begin graceful close.
+ */
+int
+muxserver_accept_control(void)
+{
+ Buffer m;
+ Channel *c;
+ int client_fd, new_fd[3], ver, allowed, window, packetmax;
+ socklen_t addrlen;
+ struct sockaddr_storage addr;
+ struct mux_session_confirm_ctx *cctx;
+ char *cmd;
+ u_int i, j, len, env_len, mux_command, flags;
+ uid_t euid;
+ gid_t egid;
+ int start_close = 0;
+
+ /*
+ * Accept connection on control socket
+ */
+ memset(&addr, 0, sizeof(addr));
+ addrlen = sizeof(addr);
+ if ((client_fd = accept(muxserver_sock,
+ (struct sockaddr*)&addr, &addrlen)) == -1) {
+ error("%s accept: %s", __func__, strerror(errno));
+ return 0;
+ }
+
+ if (getpeereid(client_fd, &euid, &egid) < 0) {
+ error("%s getpeereid failed: %s", __func__, strerror(errno));
+ close(client_fd);
+ return 0;
+ }
+ 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 0;
+ }
+
+ /* XXX handle asynchronously */
+ unset_nonblock(client_fd);
+
+ /* Read command */
+ buffer_init(&m);
+ if (ssh_msg_recv(client_fd, &m) == -1) {
+ error("%s: client msg_recv failed", __func__);
+ close(client_fd);
+ buffer_free(&m);
+ return 0;
+ }
+ if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
+ error("%s: wrong client version %d", __func__, ver);
+ buffer_free(&m);
+ close(client_fd);
+ return 0;
+ }
+
+ allowed = 1;
+ mux_command = buffer_get_int(&m);
+ flags = buffer_get_int(&m);
+
+ buffer_clear(&m);
+
+ switch (mux_command) {
+ case SSHMUX_COMMAND_OPEN:
+ if (options.control_master == SSHCTL_MASTER_ASK ||
+ options.control_master == SSHCTL_MASTER_AUTO_ASK)
+ allowed = ask_permission("Allow shared connection "
+ "to %s? ", host);
+ /* continue below */
+ break;
+ case SSHMUX_COMMAND_TERMINATE:
+ if (options.control_master == SSHCTL_MASTER_ASK ||
+ options.control_master == SSHCTL_MASTER_AUTO_ASK)
+ allowed = ask_permission("Terminate shared connection "
+ "to %s? ", host);
+ if (allowed)
+ start_close = 1;
+ /* FALLTHROUGH */
+ case SSHMUX_COMMAND_ALIVE_CHECK:
+ /* Reply for SSHMUX_COMMAND_TERMINATE and ALIVE_CHECK */
+ buffer_clear(&m);
+ buffer_put_int(&m, allowed);
+ buffer_put_int(&m, getpid());
+ if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
+ error("%s: client msg_send failed", __func__);
+ close(client_fd);
+ buffer_free(&m);
+ return start_close;
+ }
+ buffer_free(&m);
+ close(client_fd);
+ return start_close;
+ default:
+ error("Unsupported command %d", mux_command);
+ buffer_free(&m);
+ close(client_fd);
+ return 0;
+ }
+
+ /* Reply for SSHMUX_COMMAND_OPEN */
+ buffer_clear(&m);
+ buffer_put_int(&m, allowed);
+ buffer_put_int(&m, getpid());
+ if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
+ error("%s: client msg_send failed", __func__);
+ close(client_fd);
+ buffer_free(&m);
+ return 0;
+ }
+
+ if (!allowed) {
+ error("Refused control connection");
+ close(client_fd);
+ buffer_free(&m);
+ return 0;
+ }
+
+ buffer_clear(&m);
+ if (ssh_msg_recv(client_fd, &m) == -1) {
+ error("%s: client msg_recv failed", __func__);
+ close(client_fd);
+ buffer_free(&m);
+ return 0;
+ }
+ if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
+ error("%s: wrong client version %d", __func__, ver);
+ buffer_free(&m);
+ close(client_fd);
+ return 0;
+ }
+
+ cctx = xcalloc(1, sizeof(*cctx));
+ cctx->want_tty = (flags & SSHMUX_FLAG_TTY) != 0;
+ cctx->want_subsys = (flags & SSHMUX_FLAG_SUBSYS) != 0;
+ cctx->want_x_fwd = (flags & SSHMUX_FLAG_X11_FWD) != 0;
+ cctx->want_agent_fwd = (flags & SSHMUX_FLAG_AGENT_FWD) != 0;
+ cctx->term = buffer_get_string(&m, &len);
+
+ cmd = buffer_get_string(&m, &len);
+ buffer_init(&cctx->cmd);
+ buffer_append(&cctx->cmd, cmd, strlen(cmd));
+
+ env_len = buffer_get_int(&m);
+ env_len = MIN(env_len, 4096);
+ debug3("%s: receiving %d env vars", __func__, env_len);
+ if (env_len != 0) {
+ cctx->env = xcalloc(env_len + 1, sizeof(*cctx->env));
+ for (i = 0; i < env_len; i++)
+ cctx->env[i] = buffer_get_string(&m, &len);
+ cctx->env[i] = NULL;
+ }
+
+ debug2("%s: accepted tty %d, subsys %d, cmd %s", __func__,
+ cctx->want_tty, cctx->want_subsys, cmd);
+ xfree(cmd);
+
+ /* Gather fds from client */
+ for(i = 0; i < 3; i++) {
+ if ((new_fd[i] = mm_receive_fd(client_fd)) == -1) {
+ error("%s: failed to receive fd %d from slave",
+ __func__, i);
+ for (j = 0; j < i; j++)
+ close(new_fd[j]);
+ for (j = 0; j < env_len; j++)
+ xfree(cctx->env[j]);
+ if (env_len > 0)
+ xfree(cctx->env);
+ xfree(cctx->term);
+ buffer_free(&cctx->cmd);
+ close(client_fd);
+ xfree(cctx);
+ return 0;
+ }
+ }
+
+ 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));
+
+ /* This roundtrip is just for synchronisation of ttymodes */
+ buffer_clear(&m);
+ if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
+ error("%s: client msg_send failed", __func__);
+ close(client_fd);
+ close(new_fd[0]);
+ close(new_fd[1]);
+ close(new_fd[2]);
+ buffer_free(&m);
+ xfree(cctx->term);
+ if (env_len != 0) {
+ for (i = 0; i < env_len; i++)
+ xfree(cctx->env[i]);
+ xfree(cctx->env);
+ }
+ return 0;
+ }
+ 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);
+
+ window = CHAN_SES_WINDOW_DEFAULT;
+ packetmax = CHAN_SES_PACKET_DEFAULT;
+ if (cctx->want_tty) {
+ window >>= 1;
+ packetmax >>= 1;
+ }
+
+ c = channel_new("session", SSH_CHANNEL_OPENING,
+ new_fd[0], new_fd[1], new_fd[2], window, packetmax,
+ 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_open_confirm(c->self,
+ client_extra_session2_setup, cctx);
+ return 0;
+}
+
+/* ** Multiplexing client support */
+
+/* Exit signal handler */
+static void
+control_client_sighandler(int signo)
+{
+ muxclient_terminate = signo;
+}
+
+/*
+ * Relay signal handler - used to pass some signals from mux client to
+ * mux master.
+ */
+static void
+control_client_sigrelay(int signo)
+{
+ int save_errno = errno;
+
+ if (muxserver_pid > 1)
+ kill(muxserver_pid, signo);
+
+ errno = save_errno;
+}
+
+/* Check mux client environment variables before passing them to mux master. */
+static int
+env_permitted(char *env)
+{
+ int i, ret;
+ char name[1024], *cp;
+
+ if ((cp = strchr(env, '=')) == NULL || cp == env)
+ return (0);
+ ret = snprintf(name, sizeof(name), "%.*s", (int)(cp - env), env);
+ if (ret <= 0 || (size_t)ret >= sizeof(name))
+ fatal("env_permitted: name '%.100s...' too long", env);
+
+ for (i = 0; i < options.num_send_env; i++)
+ if (match_pattern(name, options.send_env[i]))
+ return (1);
+
+ return (0);
+}
+
+/* Multiplex client main loop. */
+void
+muxclient(const char *path)
+{
+ struct sockaddr_un addr;
+ int i, r, fd, sock, exitval[2], num_env, addr_len;
+ Buffer m;
+ char *term;
+ extern char **environ;
+ u_int flags;
+
+ if (muxclient_command == 0)
+ muxclient_command = SSHMUX_COMMAND_OPEN;
+
+ switch (options.control_master) {
+ case SSHCTL_MASTER_AUTO:
+ case SSHCTL_MASTER_AUTO_ASK:
+ debug("auto-mux: Trying existing master");
+ /* FALLTHROUGH */
+ case SSHCTL_MASTER_NO:
+ break;
+ default:
+ return;
+ }
+
+ memset(&addr, '\0', sizeof(addr));
+ addr.sun_family = AF_UNIX;
+ addr_len = offsetof(struct sockaddr_un, sun_path) +
+ strlen(path) + 1;
+
+ if (strlcpy(addr.sun_path, path,
+ sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
+ fatal("ControlPath too long");
+
+ if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
+ fatal("%s socket(): %s", __func__, strerror(errno));
+
+ if (connect(sock, (struct sockaddr *)&addr, addr_len) == -1) {
+ if (muxclient_command != SSHMUX_COMMAND_OPEN) {
+ fatal("Control socket connect(%.100s): %s", path,
+ strerror(errno));
+ }
+ if (errno == ENOENT)
+ debug("Control socket \"%.100s\" does not exist", path);
+ else {
+ error("Control socket connect(%.100s): %s", path,
+ strerror(errno));
+ }
+ close(sock);
+ return;
+ }
+
+ if (stdin_null_flag) {
+ if ((fd = open(_PATH_DEVNULL, O_RDONLY)) == -1)
+ fatal("open(/dev/null): %s", strerror(errno));
+ if (dup2(fd, STDIN_FILENO) == -1)
+ fatal("dup2: %s", strerror(errno));
+ if (fd > STDERR_FILENO)
+ close(fd);
+ }
+
+ term = getenv("TERM");
+
+ flags = 0;
+ if (tty_flag)
+ flags |= SSHMUX_FLAG_TTY;
+ if (subsystem_flag)
+ flags |= SSHMUX_FLAG_SUBSYS;
+ if (options.forward_x11)
+ flags |= SSHMUX_FLAG_X11_FWD;
+ if (options.forward_agent)
+ flags |= SSHMUX_FLAG_AGENT_FWD;
+
+ signal(SIGPIPE, SIG_IGN);
+
+ buffer_init(&m);
+
+ /* Send our command to server */
+ buffer_put_int(&m, muxclient_command);
+ buffer_put_int(&m, flags);
+ if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
+ fatal("%s: msg_send", __func__);
+ buffer_clear(&m);
+
+ /* Get authorisation status and PID of controlee */
+ if (ssh_msg_recv(sock, &m) == -1)
+ fatal("%s: msg_recv", __func__);
+ if (buffer_get_char(&m) != SSHMUX_VER)
+ fatal("%s: wrong version", __func__);
+ if (buffer_get_int(&m) != 1)
+ fatal("Connection to master denied");
+ muxserver_pid = buffer_get_int(&m);
+
+ buffer_clear(&m);
+
+ switch (muxclient_command) {
+ case SSHMUX_COMMAND_ALIVE_CHECK:
+ fprintf(stderr, "Master running (pid=%d)\r\n",
+ muxserver_pid);
+ exit(0);
+ case SSHMUX_COMMAND_TERMINATE:
+ fprintf(stderr, "Exit request sent.\r\n");
+ exit(0);
+ case SSHMUX_COMMAND_OPEN:
+ /* continue below */
+ break;
+ default:
+ fatal("silly muxclient_command %d", muxclient_command);
+ }
+
+ /* SSHMUX_COMMAND_OPEN */
+ buffer_put_cstring(&m, term ? term : "");
+ buffer_append(&command, "\0", 1);
+ buffer_put_cstring(&m, buffer_ptr(&command));
+
+ if (options.num_send_env == 0 || environ == NULL) {
+ buffer_put_int(&m, 0);
+ } else {
+ /* Pass environment */
+ num_env = 0;
+ for (i = 0; environ[i] != NULL; i++)
+ if (env_permitted(environ[i]))
+ num_env++; /* Count */
+
+ buffer_put_int(&m, num_env);
+
+ for (i = 0; environ[i] != NULL && num_env >= 0; i++)
+ if (env_permitted(environ[i])) {
+ num_env--;
+ buffer_put_cstring(&m, environ[i]);
+ }
+ }
+
+ if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
+ fatal("%s: msg_send", __func__);
+
+ if (mm_send_fd(sock, STDIN_FILENO) == -1 ||
+ mm_send_fd(sock, STDOUT_FILENO) == -1 ||
+ mm_send_fd(sock, STDERR_FILENO) == -1)
+ fatal("%s: send fds failed", __func__);
+
+ /* Wait for reply, so master has a chance to gather ttymodes */
+ buffer_clear(&m);
+ if (ssh_msg_recv(sock, &m) == -1)
+ fatal("%s: msg_recv", __func__);
+ if (buffer_get_char(&m) != SSHMUX_VER)
+ fatal("%s: wrong version", __func__);
+ buffer_free(&m);
+
+ signal(SIGHUP, control_client_sighandler);
+ signal(SIGINT, control_client_sighandler);
+ signal(SIGTERM, control_client_sighandler);
+ signal(SIGWINCH, control_client_sigrelay);
+
+ if (tty_flag)
+ enter_raw_mode();
+
+ /*
+ * Stick around until the controlee closes the client_fd.
+ * Before it does, it is expected to write this process' exit
+ * value (one int). This process must read the value and wait for
+ * the closure of the client_fd; if this one closes early, the
+ * multiplex master will terminate early too (possibly losing data).
+ */
+ exitval[0] = 0;
+ for (i = 0; !muxclient_terminate && i < (int)sizeof(exitval);) {
+ r = read(sock, (char *)exitval + i, sizeof(exitval) - i);
+ if (r == 0) {
+ debug2("Received EOF from master");
+ break;
+ }
+ if (r == -1) {
+ if (errno == EINTR)
+ continue;
+ fatal("%s: read %s", __func__, strerror(errno));
+ }
+ i += r;
+ }
+
+ close(sock);
+ leave_raw_mode();
+ if (i > (int)sizeof(int))
+ fatal("%s: master returned too much data (%d > %lu)",
+ __func__, i, sizeof(int));
+ if (muxclient_terminate) {
+ debug2("Exiting on signal %d", muxclient_terminate);
+ exitval[0] = 255;
+ } else if (i < (int)sizeof(int)) {
+ debug2("Control master terminated unexpectedly");
+ exitval[0] = 255;
+ } else
+ debug2("Received exit status from master %d", exitval[0]);
+
+ if (tty_flag && options.log_level != SYSLOG_LEVEL_QUIET)
+ fprintf(stderr, "Shared connection to %s closed.\r\n", host);
+
+ exit(exitval[0]);
+}
diff --git a/ssh.c b/ssh.c
index cfefade..c944d0a 100644
--- a/ssh.c
+++ b/ssh.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh.c,v 1.311 2008/05/08 13:06:11 djm Exp $ */
+/* $OpenBSD: ssh.c,v 1.312 2008/05/09 14:18:44 djm Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -49,7 +49,6 @@
#include <sys/resource.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
-#include <sys/un.h>
#include <ctype.h>
#include <errno.h>
@@ -99,7 +98,6 @@
#include "sshpty.h"
#include "match.h"
#include "msg.h"
-#include "monitor_fdpass.h"
#include "uidswap.h"
#include "version.h"
@@ -171,15 +169,9 @@
/* pid of proxycommand child process */
pid_t proxy_command_pid = 0;
-/* fd to control socket */
-int control_fd = -1;
-
-/* Multiplexing control command */
-static u_int mux_command = 0;
-
-/* Only used in control client mode */
-volatile sig_atomic_t control_client_terminate = 0;
-u_int control_server_pid = 0;
+/* mux.c */
+extern int muxserver_sock;
+extern u_int muxclient_command;
/* Prints a help message to the user. This function never returns. */
@@ -200,7 +192,10 @@
static int ssh_session(void);
static int ssh_session2(void);
static void load_public_identity_files(void);
-static void control_client(const char *path);
+
+/* from muxclient.c */
+void muxclient(const char *);
+void muxserver_listen(void);
/*
* Main program for the ssh client.
@@ -310,9 +305,9 @@
break;
case 'O':
if (strcmp(optarg, "check") == 0)
- mux_command = SSHMUX_COMMAND_ALIVE_CHECK;
+ muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
else if (strcmp(optarg, "exit") == 0)
- mux_command = SSHMUX_COMMAND_TERMINATE;
+ muxclient_command = SSHMUX_COMMAND_TERMINATE;
else
fatal("Invalid multiplex command.");
break;
@@ -683,10 +678,10 @@
"r", options.user, "l", thishost, (char *)NULL);
xfree(cp);
}
- if (mux_command != 0 && options.control_path == NULL)
+ if (muxclient_command != 0 && options.control_path == NULL)
fatal("No ControlPath specified for \"-O\" command");
if (options.control_path != NULL)
- control_client(options.control_path);
+ muxclient(options.control_path);
timeout_ms = options.connection_timeout * 1000;
@@ -809,7 +804,7 @@
exit_status = compat20 ? ssh_session2() : ssh_session();
packet_close();
- if (options.control_path != NULL && control_fd != -1)
+ if (options.control_path != NULL && muxserver_sock != -1)
unlink(options.control_path);
/*
@@ -1064,48 +1059,6 @@
}
}
-static void
-ssh_control_listener(void)
-{
- struct sockaddr_un addr;
- mode_t old_umask;
- int addr_len;
-
- if (options.control_path == NULL ||
- options.control_master == SSHCTL_MASTER_NO)
- return;
-
- debug("setting up multiplex master socket");
-
- memset(&addr, '\0', sizeof(addr));
- addr.sun_family = AF_UNIX;
- addr_len = offsetof(struct sockaddr_un, sun_path) +
- strlen(options.control_path) + 1;
-
- if (strlcpy(addr.sun_path, options.control_path,
- sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
- fatal("ControlPath too long");
-
- if ((control_fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
- fatal("%s socket(): %s", __func__, strerror(errno));
-
- old_umask = umask(0177);
- if (bind(control_fd, (struct sockaddr *)&addr, addr_len) == -1) {
- control_fd = -1;
- if (errno == EINVAL || errno == EADDRINUSE)
- fatal("ControlSocket %s already exists",
- options.control_path);
- else
- fatal("%s bind(): %s", __func__, strerror(errno));
- }
- umask(old_umask);
-
- if (listen(control_fd, 64) == -1)
- fatal("%s listen(): %s", __func__, strerror(errno));
-
- set_nonblock(control_fd);
-}
-
/* request pty/x11/agent/tcpfwd/shell for channel */
static void
ssh_session2_setup(int id, void *arg)
@@ -1204,7 +1157,7 @@
ssh_local_cmd(options.local_command);
/* Start listening for multiplex clients */
- ssh_control_listener();
+ muxserver_listen();
/* If requested, let ssh continue in the background. */
if (fork_after_authentication_flag)
@@ -1272,237 +1225,3 @@
bzero(pwdir, strlen(pwdir));
xfree(pwdir);
}
-
-static void
-control_client_sighandler(int signo)
-{
- control_client_terminate = signo;
-}
-
-static void
-control_client_sigrelay(int signo)
-{
- int save_errno = errno;
-
- if (control_server_pid > 1)
- kill(control_server_pid, signo);
-
- errno = save_errno;
-}
-
-static int
-env_permitted(char *env)
-{
- int i, ret;
- char name[1024], *cp;
-
- if ((cp = strchr(env, '=')) == NULL || cp == env)
- return (0);
- ret = snprintf(name, sizeof(name), "%.*s", (int)(cp - env), env);
- if (ret <= 0 || (size_t)ret >= sizeof(name))
- fatal("env_permitted: name '%.100s...' too long", env);
-
- for (i = 0; i < options.num_send_env; i++)
- if (match_pattern(name, options.send_env[i]))
- return (1);
-
- return (0);
-}
-
-static void
-control_client(const char *path)
-{
- struct sockaddr_un addr;
- int i, r, fd, sock, exitval[2], num_env, addr_len;
- Buffer m;
- char *term;
- extern char **environ;
- u_int flags;
-
- if (mux_command == 0)
- mux_command = SSHMUX_COMMAND_OPEN;
-
- switch (options.control_master) {
- case SSHCTL_MASTER_AUTO:
- case SSHCTL_MASTER_AUTO_ASK:
- debug("auto-mux: Trying existing master");
- /* FALLTHROUGH */
- case SSHCTL_MASTER_NO:
- break;
- default:
- return;
- }
-
- memset(&addr, '\0', sizeof(addr));
- addr.sun_family = AF_UNIX;
- addr_len = offsetof(struct sockaddr_un, sun_path) +
- strlen(path) + 1;
-
- if (strlcpy(addr.sun_path, path,
- sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
- fatal("ControlPath too long");
-
- if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
- fatal("%s socket(): %s", __func__, strerror(errno));
-
- if (connect(sock, (struct sockaddr *)&addr, addr_len) == -1) {
- if (mux_command != SSHMUX_COMMAND_OPEN) {
- fatal("Control socket connect(%.100s): %s", path,
- strerror(errno));
- }
- if (errno == ENOENT)
- debug("Control socket \"%.100s\" does not exist", path);
- else {
- error("Control socket connect(%.100s): %s", path,
- strerror(errno));
- }
- close(sock);
- return;
- }
-
- if (stdin_null_flag) {
- if ((fd = open(_PATH_DEVNULL, O_RDONLY)) == -1)
- fatal("open(/dev/null): %s", strerror(errno));
- if (dup2(fd, STDIN_FILENO) == -1)
- fatal("dup2: %s", strerror(errno));
- if (fd > STDERR_FILENO)
- close(fd);
- }
-
- term = getenv("TERM");
-
- flags = 0;
- if (tty_flag)
- flags |= SSHMUX_FLAG_TTY;
- if (subsystem_flag)
- flags |= SSHMUX_FLAG_SUBSYS;
- if (options.forward_x11)
- flags |= SSHMUX_FLAG_X11_FWD;
- if (options.forward_agent)
- flags |= SSHMUX_FLAG_AGENT_FWD;
-
- signal(SIGPIPE, SIG_IGN);
-
- buffer_init(&m);
-
- /* Send our command to server */
- buffer_put_int(&m, mux_command);
- buffer_put_int(&m, flags);
- if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
- fatal("%s: msg_send", __func__);
- buffer_clear(&m);
-
- /* Get authorisation status and PID of controlee */
- if (ssh_msg_recv(sock, &m) == -1)
- fatal("%s: msg_recv", __func__);
- if (buffer_get_char(&m) != SSHMUX_VER)
- fatal("%s: wrong version", __func__);
- if (buffer_get_int(&m) != 1)
- fatal("Connection to master denied");
- control_server_pid = buffer_get_int(&m);
-
- buffer_clear(&m);
-
- switch (mux_command) {
- case SSHMUX_COMMAND_ALIVE_CHECK:
- fprintf(stderr, "Master running (pid=%d)\r\n",
- control_server_pid);
- exit(0);
- case SSHMUX_COMMAND_TERMINATE:
- fprintf(stderr, "Exit request sent.\r\n");
- exit(0);
- case SSHMUX_COMMAND_OPEN:
- /* continue below */
- break;
- default:
- fatal("silly mux_command %d", mux_command);
- }
-
- /* SSHMUX_COMMAND_OPEN */
- buffer_put_cstring(&m, term ? term : "");
- buffer_append(&command, "\0", 1);
- buffer_put_cstring(&m, buffer_ptr(&command));
-
- if (options.num_send_env == 0 || environ == NULL) {
- buffer_put_int(&m, 0);
- } else {
- /* Pass environment */
- num_env = 0;
- for (i = 0; environ[i] != NULL; i++)
- if (env_permitted(environ[i]))
- num_env++; /* Count */
-
- buffer_put_int(&m, num_env);
-
- for (i = 0; environ[i] != NULL && num_env >= 0; i++)
- if (env_permitted(environ[i])) {
- num_env--;
- buffer_put_cstring(&m, environ[i]);
- }
- }
-
- if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
- fatal("%s: msg_send", __func__);
-
- if (mm_send_fd(sock, STDIN_FILENO) == -1 ||
- mm_send_fd(sock, STDOUT_FILENO) == -1 ||
- mm_send_fd(sock, STDERR_FILENO) == -1)
- fatal("%s: send fds failed", __func__);
-
- /* Wait for reply, so master has a chance to gather ttymodes */
- buffer_clear(&m);
- if (ssh_msg_recv(sock, &m) == -1)
- fatal("%s: msg_recv", __func__);
- if (buffer_get_char(&m) != SSHMUX_VER)
- fatal("%s: wrong version", __func__);
- buffer_free(&m);
-
- signal(SIGHUP, control_client_sighandler);
- signal(SIGINT, control_client_sighandler);
- signal(SIGTERM, control_client_sighandler);
- signal(SIGWINCH, control_client_sigrelay);
-
- if (tty_flag)
- enter_raw_mode();
-
- /*
- * Stick around until the controlee closes the client_fd.
- * Before it does, it is expected to write this process' exit
- * value (one int). This process must read the value and wait for
- * the closure of the client_fd; if this one closes early, the
- * multiplex master will terminate early too (possibly losing data).
- */
- exitval[0] = 0;
- for (i = 0; !control_client_terminate && i < (int)sizeof(exitval);) {
- r = read(sock, (char *)exitval + i, sizeof(exitval) - i);
- if (r == 0) {
- debug2("Received EOF from master");
- break;
- }
- if (r == -1) {
- if (errno == EINTR)
- continue;
- fatal("%s: read %s", __func__, strerror(errno));
- }
- i += r;
- }
-
- close(sock);
- leave_raw_mode();
- if (i > (int)sizeof(int))
- fatal("%s: master returned too much data (%d > %lu)",
- __func__, i, sizeof(int));
- if (control_client_terminate) {
- debug2("Exiting on signal %d", control_client_terminate);
- exitval[0] = 255;
- } else if (i < (int)sizeof(int)) {
- debug2("Control master terminated unexpectedly");
- exitval[0] = 255;
- } else
- debug2("Received exit status from master %d", exitval[0]);
-
- if (tty_flag && options.log_level != SYSLOG_LEVEL_QUIET)
- fprintf(stderr, "Shared connection to %s closed.\r\n", host);
-
- exit(exitval[0]);
-}