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-rw-r--r--ChangeLog8
-rw-r--r--Makefile.in4
-rw-r--r--clientloop.c308
-rw-r--r--clientloop.h20
-rw-r--r--mux.c646
-rw-r--r--ssh.c309
6 files changed, 699 insertions, 596 deletions
diff --git a/ChangeLog b/ChangeLog
index 9e683143a..90ee86ac8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -111,6 +111,12 @@
111 was to try the first address and give up. 111 was to try the first address and give up.
112 Reported by stig AT venaas.com in bz#343 112 Reported by stig AT venaas.com in bz#343
113 great feedback and ok markus@ 113 great feedback and ok markus@
114 - djm@cvs.openbsd.org 2008/05/09 14:18:44
115 [clientloop.c clientloop.h ssh.c mux.c]
116 tidy up session multiplexing code, moving it into its own file and
117 making the function names more consistent - making ssh.c and
118 clientloop.c a fair bit more readable.
119 ok markus@
114 120
11520080403 12120080403
116 - (djm) [openbsd-compat/bsd-poll.c] Include stdlib.h to avoid compile- 122 - (djm) [openbsd-compat/bsd-poll.c] Include stdlib.h to avoid compile-
@@ -3971,4 +3977,4 @@
3971 OpenServer 6 and add osr5bigcrypt support so when someone migrates 3977 OpenServer 6 and add osr5bigcrypt support so when someone migrates
3972 passwords between UnixWare and OpenServer they will still work. OK dtucker@ 3978 passwords between UnixWare and OpenServer they will still work. OK dtucker@
3973 3979
3974$Id: ChangeLog,v 1.4925 2008/05/19 05:37:09 djm Exp $ 3980$Id: ChangeLog,v 1.4926 2008/05/19 06:00:08 djm Exp $
diff --git a/Makefile.in b/Makefile.in
index 6b488feca..b57b9b72d 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -1,4 +1,4 @@
1# $Id: Makefile.in,v 1.289 2008/03/13 01:41:31 djm Exp $ 1# $Id: Makefile.in,v 1.290 2008/05/19 06:00:08 djm Exp $
2 2
3# uncomment if you run a non bourne compatable shell. Ie. csh 3# uncomment if you run a non bourne compatable shell. Ie. csh
4#SHELL = @SH@ 4#SHELL = @SH@
@@ -74,7 +74,7 @@ LIBSSH_OBJS=acss.o authfd.o authfile.o bufaux.o bufbn.o buffer.o \
74 entropy.o scard-opensc.o gss-genr.o umac.o 74 entropy.o scard-opensc.o gss-genr.o umac.o
75 75
76SSHOBJS= ssh.o readconf.o clientloop.o sshtty.o \ 76SSHOBJS= ssh.o readconf.o clientloop.o sshtty.o \
77 sshconnect.o sshconnect1.o sshconnect2.o 77 sshconnect.o sshconnect1.o sshconnect2.o mux.o
78 78
79SSHDOBJS=sshd.o auth-rhosts.o auth-passwd.o auth-rsa.o auth-rh-rsa.o \ 79SSHDOBJS=sshd.o auth-rhosts.o auth-passwd.o auth-rsa.o auth-rh-rsa.o \
80 sshpty.o sshlogin.o servconf.o serverloop.o \ 80 sshpty.o sshlogin.o servconf.o serverloop.o \
diff --git a/clientloop.c b/clientloop.c
index 7bd1af60c..c87aa5a0a 100644
--- a/clientloop.c
+++ b/clientloop.c
@@ -1,4 +1,4 @@
1/* $OpenBSD: clientloop.c,v 1.191 2008/05/09 04:55:56 djm Exp $ */ 1/* $OpenBSD: clientloop.c,v 1.192 2008/05/09 14:18:44 djm Exp $ */
2/* 2/*
3 * Author: Tatu Ylonen <ylo@cs.hut.fi> 3 * Author: Tatu Ylonen <ylo@cs.hut.fi>
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -121,7 +121,7 @@ extern int stdin_null_flag;
121extern int no_shell_flag; 121extern int no_shell_flag;
122 122
123/* Control socket */ 123/* Control socket */
124extern int control_fd; 124extern int muxserver_sock;
125 125
126/* 126/*
127 * Name of the host we are connecting to. This is the name given on the 127 * Name of the host we are connecting to. This is the name given on the
@@ -162,17 +162,6 @@ static int session_closed = 0; /* In SSH2: login session closed. */
162static void client_init_dispatch(void); 162static void client_init_dispatch(void);
163int session_ident = -1; 163int session_ident = -1;
164 164
165struct confirm_ctx {
166 int want_tty;
167 int want_subsys;
168 int want_x_fwd;
169 int want_agent_fwd;
170 Buffer cmd;
171 char *term;
172 struct termios tio;
173 char **env;
174};
175
176struct channel_reply_ctx { 165struct channel_reply_ctx {
177 const char *request_type; 166 const char *request_type;
178 int id, do_close; 167 int id, do_close;
@@ -538,8 +527,8 @@ client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
538 if (packet_have_data_to_write()) 527 if (packet_have_data_to_write())
539 FD_SET(connection_out, *writesetp); 528 FD_SET(connection_out, *writesetp);
540 529
541 if (control_fd != -1) 530 if (muxserver_sock != -1)
542 FD_SET(control_fd, *readsetp); 531 FD_SET(muxserver_sock, *readsetp);
543 532
544 /* 533 /*
545 * Wait for something to happen. This will suspend the process until 534 * Wait for something to happen. This will suspend the process until
@@ -707,284 +696,6 @@ client_expect_confirm(int id, const char *request, int do_close)
707} 696}
708 697
709static void 698static void
710client_extra_session2_setup(int id, void *arg)
711{
712 struct confirm_ctx *cctx = arg;
713 const char *display;
714 Channel *c;
715 int i;
716
717 if (cctx == NULL)
718 fatal("%s: cctx == NULL", __func__);
719 if ((c = channel_lookup(id)) == NULL)
720 fatal("%s: no channel for id %d", __func__, id);
721
722 display = getenv("DISPLAY");
723 if (cctx->want_x_fwd && options.forward_x11 && display != NULL) {
724 char *proto, *data;
725 /* Get reasonable local authentication information. */
726 client_x11_get_proto(display, options.xauth_location,
727 options.forward_x11_trusted, &proto, &data);
728 /* Request forwarding with authentication spoofing. */
729 debug("Requesting X11 forwarding with authentication spoofing.");
730 x11_request_forwarding_with_spoofing(id, display, proto, data);
731 /* XXX wait for reply */
732 }
733
734 if (cctx->want_agent_fwd && options.forward_agent) {
735 debug("Requesting authentication agent forwarding.");
736 channel_request_start(id, "auth-agent-req@openssh.com", 0);
737 packet_send();
738 }
739
740 client_session2_setup(id, cctx->want_tty, cctx->want_subsys,
741 cctx->term, &cctx->tio, c->rfd, &cctx->cmd, cctx->env);
742
743 c->open_confirm_ctx = NULL;
744 buffer_free(&cctx->cmd);
745 xfree(cctx->term);
746 if (cctx->env != NULL) {
747 for (i = 0; cctx->env[i] != NULL; i++)
748 xfree(cctx->env[i]);
749 xfree(cctx->env);
750 }
751 xfree(cctx);
752}
753
754static void
755client_process_control(fd_set *readset)
756{
757 Buffer m;
758 Channel *c;
759 int client_fd, new_fd[3], ver, allowed, window, packetmax;
760 socklen_t addrlen;
761 struct sockaddr_storage addr;
762 struct confirm_ctx *cctx;
763 char *cmd;
764 u_int i, j, len, env_len, command, flags;
765 uid_t euid;
766 gid_t egid;
767
768 /*
769 * Accept connection on control socket
770 */
771 if (control_fd == -1 || !FD_ISSET(control_fd, readset))
772 return;
773
774 memset(&addr, 0, sizeof(addr));
775 addrlen = sizeof(addr);
776 if ((client_fd = accept(control_fd,
777 (struct sockaddr*)&addr, &addrlen)) == -1) {
778 error("%s accept: %s", __func__, strerror(errno));
779 return;
780 }
781
782 if (getpeereid(client_fd, &euid, &egid) < 0) {
783 error("%s getpeereid failed: %s", __func__, strerror(errno));
784 close(client_fd);
785 return;
786 }
787 if ((euid != 0) && (getuid() != euid)) {
788 error("control mode uid mismatch: peer euid %u != uid %u",
789 (u_int) euid, (u_int) getuid());
790 close(client_fd);
791 return;
792 }
793
794 unset_nonblock(client_fd);
795
796 /* Read command */
797 buffer_init(&m);
798 if (ssh_msg_recv(client_fd, &m) == -1) {
799 error("%s: client msg_recv failed", __func__);
800 close(client_fd);
801 buffer_free(&m);
802 return;
803 }
804 if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
805 error("%s: wrong client version %d", __func__, ver);
806 buffer_free(&m);
807 close(client_fd);
808 return;
809 }
810
811 allowed = 1;
812 command = buffer_get_int(&m);
813 flags = buffer_get_int(&m);
814
815 buffer_clear(&m);
816
817 switch (command) {
818 case SSHMUX_COMMAND_OPEN:
819 if (options.control_master == SSHCTL_MASTER_ASK ||
820 options.control_master == SSHCTL_MASTER_AUTO_ASK)
821 allowed = ask_permission("Allow shared connection "
822 "to %s? ", host);
823 /* continue below */
824 break;
825 case SSHMUX_COMMAND_TERMINATE:
826 if (options.control_master == SSHCTL_MASTER_ASK ||
827 options.control_master == SSHCTL_MASTER_AUTO_ASK)
828 allowed = ask_permission("Terminate shared connection "
829 "to %s? ", host);
830 if (allowed)
831 quit_pending = 1;
832 /* FALLTHROUGH */
833 case SSHMUX_COMMAND_ALIVE_CHECK:
834 /* Reply for SSHMUX_COMMAND_TERMINATE and ALIVE_CHECK */
835 buffer_clear(&m);
836 buffer_put_int(&m, allowed);
837 buffer_put_int(&m, getpid());
838 if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
839 error("%s: client msg_send failed", __func__);
840 close(client_fd);
841 buffer_free(&m);
842 return;
843 }
844 buffer_free(&m);
845 close(client_fd);
846 return;
847 default:
848 error("Unsupported command %d", command);
849 buffer_free(&m);
850 close(client_fd);
851 return;
852 }
853
854 /* Reply for SSHMUX_COMMAND_OPEN */
855 buffer_clear(&m);
856 buffer_put_int(&m, allowed);
857 buffer_put_int(&m, getpid());
858 if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
859 error("%s: client msg_send failed", __func__);
860 close(client_fd);
861 buffer_free(&m);
862 return;
863 }
864
865 if (!allowed) {
866 error("Refused control connection");
867 close(client_fd);
868 buffer_free(&m);
869 return;
870 }
871
872 buffer_clear(&m);
873 if (ssh_msg_recv(client_fd, &m) == -1) {
874 error("%s: client msg_recv failed", __func__);
875 close(client_fd);
876 buffer_free(&m);
877 return;
878 }
879 if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
880 error("%s: wrong client version %d", __func__, ver);
881 buffer_free(&m);
882 close(client_fd);
883 return;
884 }
885
886 cctx = xcalloc(1, sizeof(*cctx));
887 cctx->want_tty = (flags & SSHMUX_FLAG_TTY) != 0;
888 cctx->want_subsys = (flags & SSHMUX_FLAG_SUBSYS) != 0;
889 cctx->want_x_fwd = (flags & SSHMUX_FLAG_X11_FWD) != 0;
890 cctx->want_agent_fwd = (flags & SSHMUX_FLAG_AGENT_FWD) != 0;
891 cctx->term = buffer_get_string(&m, &len);
892
893 cmd = buffer_get_string(&m, &len);
894 buffer_init(&cctx->cmd);
895 buffer_append(&cctx->cmd, cmd, strlen(cmd));
896
897 env_len = buffer_get_int(&m);
898 env_len = MIN(env_len, 4096);
899 debug3("%s: receiving %d env vars", __func__, env_len);
900 if (env_len != 0) {
901 cctx->env = xcalloc(env_len + 1, sizeof(*cctx->env));
902 for (i = 0; i < env_len; i++)
903 cctx->env[i] = buffer_get_string(&m, &len);
904 cctx->env[i] = NULL;
905 }
906
907 debug2("%s: accepted tty %d, subsys %d, cmd %s", __func__,
908 cctx->want_tty, cctx->want_subsys, cmd);
909 xfree(cmd);
910
911 /* Gather fds from client */
912 for(i = 0; i < 3; i++) {
913 if ((new_fd[i] = mm_receive_fd(client_fd)) == -1) {
914 error("%s: failed to receive fd %d from slave",
915 __func__, i);
916 for (j = 0; j < i; j++)
917 close(new_fd[j]);
918 for (j = 0; j < env_len; j++)
919 xfree(cctx->env[j]);
920 if (env_len > 0)
921 xfree(cctx->env);
922 xfree(cctx->term);
923 buffer_free(&cctx->cmd);
924 close(client_fd);
925 xfree(cctx);
926 return;
927 }
928 }
929
930 debug2("%s: got fds stdin %d, stdout %d, stderr %d", __func__,
931 new_fd[0], new_fd[1], new_fd[2]);
932
933 /* Try to pick up ttymodes from client before it goes raw */
934 if (cctx->want_tty && tcgetattr(new_fd[0], &cctx->tio) == -1)
935 error("%s: tcgetattr: %s", __func__, strerror(errno));
936
937 /* This roundtrip is just for synchronisation of ttymodes */
938 buffer_clear(&m);
939 if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
940 error("%s: client msg_send failed", __func__);
941 close(client_fd);
942 close(new_fd[0]);
943 close(new_fd[1]);
944 close(new_fd[2]);
945 buffer_free(&m);
946 xfree(cctx->term);
947 if (env_len != 0) {
948 for (i = 0; i < env_len; i++)
949 xfree(cctx->env[i]);
950 xfree(cctx->env);
951 }
952 return;
953 }
954 buffer_free(&m);
955
956 /* enable nonblocking unless tty */
957 if (!isatty(new_fd[0]))
958 set_nonblock(new_fd[0]);
959 if (!isatty(new_fd[1]))
960 set_nonblock(new_fd[1]);
961 if (!isatty(new_fd[2]))
962 set_nonblock(new_fd[2]);
963
964 set_nonblock(client_fd);
965
966 window = CHAN_SES_WINDOW_DEFAULT;
967 packetmax = CHAN_SES_PACKET_DEFAULT;
968 if (cctx->want_tty) {
969 window >>= 1;
970 packetmax >>= 1;
971 }
972
973 c = channel_new("session", SSH_CHANNEL_OPENING,
974 new_fd[0], new_fd[1], new_fd[2], window, packetmax,
975 CHAN_EXTENDED_WRITE, "client-session", /*nonblock*/0);
976
977 /* XXX */
978 c->ctl_fd = client_fd;
979
980 debug3("%s: channel_new: %d", __func__, c->self);
981
982 channel_send_open(c->self);
983 channel_register_open_confirm(c->self,
984 client_extra_session2_setup, cctx);
985}
986
987static void
988process_cmdline(void) 699process_cmdline(void)
989{ 700{
990 void (*handler)(int); 701 void (*handler)(int);
@@ -1448,8 +1159,8 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1448 connection_in = packet_get_connection_in(); 1159 connection_in = packet_get_connection_in();
1449 connection_out = packet_get_connection_out(); 1160 connection_out = packet_get_connection_out();
1450 max_fd = MAX(connection_in, connection_out); 1161 max_fd = MAX(connection_in, connection_out);
1451 if (control_fd != -1) 1162 if (muxserver_sock != -1)
1452 max_fd = MAX(max_fd, control_fd); 1163 max_fd = MAX(max_fd, muxserver_sock);
1453 1164
1454 if (!compat20) { 1165 if (!compat20) {
1455 /* enable nonblocking unless tty */ 1166 /* enable nonblocking unless tty */
@@ -1569,7 +1280,10 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1569 client_process_net_input(readset); 1280 client_process_net_input(readset);
1570 1281
1571 /* Accept control connections. */ 1282 /* Accept control connections. */
1572 client_process_control(readset); 1283 if (muxserver_sock != -1 &&FD_ISSET(muxserver_sock, readset)) {
1284 if (muxserver_accept_control())
1285 quit_pending = 1;
1286 }
1573 1287
1574 if (quit_pending) 1288 if (quit_pending)
1575 break; 1289 break;
@@ -2157,7 +1871,7 @@ cleanup_exit(int i)
2157{ 1871{
2158 leave_raw_mode(); 1872 leave_raw_mode();
2159 leave_non_blocking(); 1873 leave_non_blocking();
2160 if (options.control_path != NULL && control_fd != -1) 1874 if (options.control_path != NULL && muxserver_sock != -1)
2161 unlink(options.control_path); 1875 unlink(options.control_path);
2162 _exit(i); 1876 _exit(i);
2163} 1877}
diff --git a/clientloop.h b/clientloop.h
index cb2d7c089..6f8e70123 100644
--- a/clientloop.h
+++ b/clientloop.h
@@ -1,4 +1,4 @@
1/* $OpenBSD: clientloop.h,v 1.18 2008/05/08 13:06:11 djm Exp $ */ 1/* $OpenBSD: clientloop.h,v 1.19 2008/05/09 14:18:44 djm Exp $ */
2 2
3/* 3/*
4 * Author: Tatu Ylonen <ylo@cs.hut.fi> 4 * Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -58,3 +58,21 @@ int client_request_tun_fwd(int, int, int);
58#define SSHMUX_FLAG_SUBSYS (1<<1) /* Subsystem request on open */ 58#define SSHMUX_FLAG_SUBSYS (1<<1) /* Subsystem request on open */
59#define SSHMUX_FLAG_X11_FWD (1<<2) /* Request X11 forwarding */ 59#define SSHMUX_FLAG_X11_FWD (1<<2) /* Request X11 forwarding */
60#define SSHMUX_FLAG_AGENT_FWD (1<<3) /* Request agent forwarding */ 60#define SSHMUX_FLAG_AGENT_FWD (1<<3) /* Request agent forwarding */
61
62/* Multiplexing routines */
63
64struct mux_session_confirm_ctx {
65 int want_tty;
66 int want_subsys;
67 int want_x_fwd;
68 int want_agent_fwd;
69 Buffer cmd;
70 char *term;
71 struct termios tio;
72 char **env;
73};
74
75/* mux.c */
76void muxserver_listen(void);
77int muxserver_accept_control(void);
78void muxclient(const char *);
diff --git a/mux.c b/mux.c
new file mode 100644
index 000000000..78ba63153
--- /dev/null
+++ b/mux.c
@@ -0,0 +1,646 @@
1/* $OpenBSD: mux.c,v 1.1 2008/05/09 14:18:44 djm Exp $ */
2/*
3 * Copyright (c) 2002-2008 Damien Miller <djm@openbsd.org>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18/* ssh session multiplexing support */
19
20#include <sys/types.h>
21#include <sys/param.h>
22#include <sys/stat.h>
23#include <sys/socket.h>
24#include <sys/un.h>
25
26#include <errno.h>
27#include <fcntl.h>
28#include <signal.h>
29#include <stdarg.h>
30#include <stddef.h>
31#include <stdlib.h>
32#include <stdio.h>
33#include <string.h>
34#include <unistd.h>
35#include <util.h>
36#include <paths.h>
37
38#include "openbsd-compat/sys-queue.h"
39#include "xmalloc.h"
40#include "log.h"
41#include "ssh.h"
42#include "pathnames.h"
43#include "misc.h"
44#include "match.h"
45#include "buffer.h"
46#include "channels.h"
47#include "msg.h"
48#include "packet.h"
49#include "monitor_fdpass.h"
50#include "sshpty.h"
51#include "key.h"
52#include "readconf.h"
53#include "clientloop.h"
54
55/* from ssh.c */
56extern int tty_flag;
57extern Options options;
58extern int stdin_null_flag;
59extern char *host;
60int subsystem_flag;
61extern Buffer command;
62
63/* fd to control socket */
64int muxserver_sock = -1;
65
66/* Multiplexing control command */
67u_int muxclient_command = 0;
68
69/* Set when signalled. */
70static volatile sig_atomic_t muxclient_terminate = 0;
71
72/* PID of multiplex server */
73static u_int muxserver_pid = 0;
74
75
76/* ** Multiplexing master support */
77
78/* Prepare a mux master to listen on a Unix domain socket. */
79void
80muxserver_listen(void)
81{
82 struct sockaddr_un addr;
83 mode_t old_umask;
84 int addr_len;
85
86 if (options.control_path == NULL ||
87 options.control_master == SSHCTL_MASTER_NO)
88 return;
89
90 debug("setting up multiplex master socket");
91
92 memset(&addr, '\0', sizeof(addr));
93 addr.sun_family = AF_UNIX;
94 addr_len = offsetof(struct sockaddr_un, sun_path) +
95 strlen(options.control_path) + 1;
96
97 if (strlcpy(addr.sun_path, options.control_path,
98 sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
99 fatal("ControlPath too long");
100
101 if ((muxserver_sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
102 fatal("%s socket(): %s", __func__, strerror(errno));
103
104 old_umask = umask(0177);
105 if (bind(muxserver_sock, (struct sockaddr *)&addr, addr_len) == -1) {
106 muxserver_sock = -1;
107 if (errno == EINVAL || errno == EADDRINUSE)
108 fatal("ControlSocket %s already exists",
109 options.control_path);
110 else
111 fatal("%s bind(): %s", __func__, strerror(errno));
112 }
113 umask(old_umask);
114
115 if (listen(muxserver_sock, 64) == -1)
116 fatal("%s listen(): %s", __func__, strerror(errno));
117
118 set_nonblock(muxserver_sock);
119}
120
121/* Callback on open confirmation in mux master for a mux client session. */
122static void
123client_extra_session2_setup(int id, void *arg)
124{
125 struct mux_session_confirm_ctx *cctx = arg;
126 const char *display;
127 Channel *c;
128 int i;
129
130 if (cctx == NULL)
131 fatal("%s: cctx == NULL", __func__);
132 if ((c = channel_lookup(id)) == NULL)
133 fatal("%s: no channel for id %d", __func__, id);
134
135 display = getenv("DISPLAY");
136 if (cctx->want_x_fwd && options.forward_x11 && display != NULL) {
137 char *proto, *data;
138 /* Get reasonable local authentication information. */
139 client_x11_get_proto(display, options.xauth_location,
140 options.forward_x11_trusted, &proto, &data);
141 /* Request forwarding with authentication spoofing. */
142 debug("Requesting X11 forwarding with authentication spoofing.");
143 x11_request_forwarding_with_spoofing(id, display, proto, data);
144 /* XXX wait for reply */
145 }
146
147 if (cctx->want_agent_fwd && options.forward_agent) {
148 debug("Requesting authentication agent forwarding.");
149 channel_request_start(id, "auth-agent-req@openssh.com", 0);
150 packet_send();
151 }
152
153 client_session2_setup(id, cctx->want_tty, cctx->want_subsys,
154 cctx->term, &cctx->tio, c->rfd, &cctx->cmd, cctx->env);
155
156 c->open_confirm_ctx = NULL;
157 buffer_free(&cctx->cmd);
158 xfree(cctx->term);
159 if (cctx->env != NULL) {
160 for (i = 0; cctx->env[i] != NULL; i++)
161 xfree(cctx->env[i]);
162 xfree(cctx->env);
163 }
164 xfree(cctx);
165}
166
167/*
168 * Accept a connection on the mux master socket and process the
169 * client's request. Returns flag indicating whether mux master should
170 * begin graceful close.
171 */
172int
173muxserver_accept_control(void)
174{
175 Buffer m;
176 Channel *c;
177 int client_fd, new_fd[3], ver, allowed, window, packetmax;
178 socklen_t addrlen;
179 struct sockaddr_storage addr;
180 struct mux_session_confirm_ctx *cctx;
181 char *cmd;
182 u_int i, j, len, env_len, mux_command, flags;
183 uid_t euid;
184 gid_t egid;
185 int start_close = 0;
186
187 /*
188 * Accept connection on control socket
189 */
190 memset(&addr, 0, sizeof(addr));
191 addrlen = sizeof(addr);
192 if ((client_fd = accept(muxserver_sock,
193 (struct sockaddr*)&addr, &addrlen)) == -1) {
194 error("%s accept: %s", __func__, strerror(errno));
195 return 0;
196 }
197
198 if (getpeereid(client_fd, &euid, &egid) < 0) {
199 error("%s getpeereid failed: %s", __func__, strerror(errno));
200 close(client_fd);
201 return 0;
202 }
203 if ((euid != 0) && (getuid() != euid)) {
204 error("control mode uid mismatch: peer euid %u != uid %u",
205 (u_int) euid, (u_int) getuid());
206 close(client_fd);
207 return 0;
208 }
209
210 /* XXX handle asynchronously */
211 unset_nonblock(client_fd);
212
213 /* Read command */
214 buffer_init(&m);
215 if (ssh_msg_recv(client_fd, &m) == -1) {
216 error("%s: client msg_recv failed", __func__);
217 close(client_fd);
218 buffer_free(&m);
219 return 0;
220 }
221 if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
222 error("%s: wrong client version %d", __func__, ver);
223 buffer_free(&m);
224 close(client_fd);
225 return 0;
226 }
227
228 allowed = 1;
229 mux_command = buffer_get_int(&m);
230 flags = buffer_get_int(&m);
231
232 buffer_clear(&m);
233
234 switch (mux_command) {
235 case SSHMUX_COMMAND_OPEN:
236 if (options.control_master == SSHCTL_MASTER_ASK ||
237 options.control_master == SSHCTL_MASTER_AUTO_ASK)
238 allowed = ask_permission("Allow shared connection "
239 "to %s? ", host);
240 /* continue below */
241 break;
242 case SSHMUX_COMMAND_TERMINATE:
243 if (options.control_master == SSHCTL_MASTER_ASK ||
244 options.control_master == SSHCTL_MASTER_AUTO_ASK)
245 allowed = ask_permission("Terminate shared connection "
246 "to %s? ", host);
247 if (allowed)
248 start_close = 1;
249 /* FALLTHROUGH */
250 case SSHMUX_COMMAND_ALIVE_CHECK:
251 /* Reply for SSHMUX_COMMAND_TERMINATE and ALIVE_CHECK */
252 buffer_clear(&m);
253 buffer_put_int(&m, allowed);
254 buffer_put_int(&m, getpid());
255 if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
256 error("%s: client msg_send failed", __func__);
257 close(client_fd);
258 buffer_free(&m);
259 return start_close;
260 }
261 buffer_free(&m);
262 close(client_fd);
263 return start_close;
264 default:
265 error("Unsupported command %d", mux_command);
266 buffer_free(&m);
267 close(client_fd);
268 return 0;
269 }
270
271 /* Reply for SSHMUX_COMMAND_OPEN */
272 buffer_clear(&m);
273 buffer_put_int(&m, allowed);
274 buffer_put_int(&m, getpid());
275 if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
276 error("%s: client msg_send failed", __func__);
277 close(client_fd);
278 buffer_free(&m);
279 return 0;
280 }
281
282 if (!allowed) {
283 error("Refused control connection");
284 close(client_fd);
285 buffer_free(&m);
286 return 0;
287 }
288
289 buffer_clear(&m);
290 if (ssh_msg_recv(client_fd, &m) == -1) {
291 error("%s: client msg_recv failed", __func__);
292 close(client_fd);
293 buffer_free(&m);
294 return 0;
295 }
296 if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
297 error("%s: wrong client version %d", __func__, ver);
298 buffer_free(&m);
299 close(client_fd);
300 return 0;
301 }
302
303 cctx = xcalloc(1, sizeof(*cctx));
304 cctx->want_tty = (flags & SSHMUX_FLAG_TTY) != 0;
305 cctx->want_subsys = (flags & SSHMUX_FLAG_SUBSYS) != 0;
306 cctx->want_x_fwd = (flags & SSHMUX_FLAG_X11_FWD) != 0;
307 cctx->want_agent_fwd = (flags & SSHMUX_FLAG_AGENT_FWD) != 0;
308 cctx->term = buffer_get_string(&m, &len);
309
310 cmd = buffer_get_string(&m, &len);
311 buffer_init(&cctx->cmd);
312 buffer_append(&cctx->cmd, cmd, strlen(cmd));
313
314 env_len = buffer_get_int(&m);
315 env_len = MIN(env_len, 4096);
316 debug3("%s: receiving %d env vars", __func__, env_len);
317 if (env_len != 0) {
318 cctx->env = xcalloc(env_len + 1, sizeof(*cctx->env));
319 for (i = 0; i < env_len; i++)
320 cctx->env[i] = buffer_get_string(&m, &len);
321 cctx->env[i] = NULL;
322 }
323
324 debug2("%s: accepted tty %d, subsys %d, cmd %s", __func__,
325 cctx->want_tty, cctx->want_subsys, cmd);
326 xfree(cmd);
327
328 /* Gather fds from client */
329 for(i = 0; i < 3; i++) {
330 if ((new_fd[i] = mm_receive_fd(client_fd)) == -1) {
331 error("%s: failed to receive fd %d from slave",
332 __func__, i);
333 for (j = 0; j < i; j++)
334 close(new_fd[j]);
335 for (j = 0; j < env_len; j++)
336 xfree(cctx->env[j]);
337 if (env_len > 0)
338 xfree(cctx->env);
339 xfree(cctx->term);
340 buffer_free(&cctx->cmd);
341 close(client_fd);
342 xfree(cctx);
343 return 0;
344 }
345 }
346
347 debug2("%s: got fds stdin %d, stdout %d, stderr %d", __func__,
348 new_fd[0], new_fd[1], new_fd[2]);
349
350 /* Try to pick up ttymodes from client before it goes raw */
351 if (cctx->want_tty && tcgetattr(new_fd[0], &cctx->tio) == -1)
352 error("%s: tcgetattr: %s", __func__, strerror(errno));
353
354 /* This roundtrip is just for synchronisation of ttymodes */
355 buffer_clear(&m);
356 if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
357 error("%s: client msg_send failed", __func__);
358 close(client_fd);
359 close(new_fd[0]);
360 close(new_fd[1]);
361 close(new_fd[2]);
362 buffer_free(&m);
363 xfree(cctx->term);
364 if (env_len != 0) {
365 for (i = 0; i < env_len; i++)
366 xfree(cctx->env[i]);
367 xfree(cctx->env);
368 }
369 return 0;
370 }
371 buffer_free(&m);
372
373 /* enable nonblocking unless tty */
374 if (!isatty(new_fd[0]))
375 set_nonblock(new_fd[0]);
376 if (!isatty(new_fd[1]))
377 set_nonblock(new_fd[1]);
378 if (!isatty(new_fd[2]))
379 set_nonblock(new_fd[2]);
380
381 set_nonblock(client_fd);
382
383 window = CHAN_SES_WINDOW_DEFAULT;
384 packetmax = CHAN_SES_PACKET_DEFAULT;
385 if (cctx->want_tty) {
386 window >>= 1;
387 packetmax >>= 1;
388 }
389
390 c = channel_new("session", SSH_CHANNEL_OPENING,
391 new_fd[0], new_fd[1], new_fd[2], window, packetmax,
392 CHAN_EXTENDED_WRITE, "client-session", /*nonblock*/0);
393
394 /* XXX */
395 c->ctl_fd = client_fd;
396
397 debug3("%s: channel_new: %d", __func__, c->self);
398
399 channel_send_open(c->self);
400 channel_register_open_confirm(c->self,
401 client_extra_session2_setup, cctx);
402 return 0;
403}
404
405/* ** Multiplexing client support */
406
407/* Exit signal handler */
408static void
409control_client_sighandler(int signo)
410{
411 muxclient_terminate = signo;
412}
413
414/*
415 * Relay signal handler - used to pass some signals from mux client to
416 * mux master.
417 */
418static void
419control_client_sigrelay(int signo)
420{
421 int save_errno = errno;
422
423 if (muxserver_pid > 1)
424 kill(muxserver_pid, signo);
425
426 errno = save_errno;
427}
428
429/* Check mux client environment variables before passing them to mux master. */
430static int
431env_permitted(char *env)
432{
433 int i, ret;
434 char name[1024], *cp;
435
436 if ((cp = strchr(env, '=')) == NULL || cp == env)
437 return (0);
438 ret = snprintf(name, sizeof(name), "%.*s", (int)(cp - env), env);
439 if (ret <= 0 || (size_t)ret >= sizeof(name))
440 fatal("env_permitted: name '%.100s...' too long", env);
441
442 for (i = 0; i < options.num_send_env; i++)
443 if (match_pattern(name, options.send_env[i]))
444 return (1);
445
446 return (0);
447}
448
449/* Multiplex client main loop. */
450void
451muxclient(const char *path)
452{
453 struct sockaddr_un addr;
454 int i, r, fd, sock, exitval[2], num_env, addr_len;
455 Buffer m;
456 char *term;
457 extern char **environ;
458 u_int flags;
459
460 if (muxclient_command == 0)
461 muxclient_command = SSHMUX_COMMAND_OPEN;
462
463 switch (options.control_master) {
464 case SSHCTL_MASTER_AUTO:
465 case SSHCTL_MASTER_AUTO_ASK:
466 debug("auto-mux: Trying existing master");
467 /* FALLTHROUGH */
468 case SSHCTL_MASTER_NO:
469 break;
470 default:
471 return;
472 }
473
474 memset(&addr, '\0', sizeof(addr));
475 addr.sun_family = AF_UNIX;
476 addr_len = offsetof(struct sockaddr_un, sun_path) +
477 strlen(path) + 1;
478
479 if (strlcpy(addr.sun_path, path,
480 sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
481 fatal("ControlPath too long");
482
483 if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
484 fatal("%s socket(): %s", __func__, strerror(errno));
485
486 if (connect(sock, (struct sockaddr *)&addr, addr_len) == -1) {
487 if (muxclient_command != SSHMUX_COMMAND_OPEN) {
488 fatal("Control socket connect(%.100s): %s", path,
489 strerror(errno));
490 }
491 if (errno == ENOENT)
492 debug("Control socket \"%.100s\" does not exist", path);
493 else {
494 error("Control socket connect(%.100s): %s", path,
495 strerror(errno));
496 }
497 close(sock);
498 return;
499 }
500
501 if (stdin_null_flag) {
502 if ((fd = open(_PATH_DEVNULL, O_RDONLY)) == -1)
503 fatal("open(/dev/null): %s", strerror(errno));
504 if (dup2(fd, STDIN_FILENO) == -1)
505 fatal("dup2: %s", strerror(errno));
506 if (fd > STDERR_FILENO)
507 close(fd);
508 }
509
510 term = getenv("TERM");
511
512 flags = 0;
513 if (tty_flag)
514 flags |= SSHMUX_FLAG_TTY;
515 if (subsystem_flag)
516 flags |= SSHMUX_FLAG_SUBSYS;
517 if (options.forward_x11)
518 flags |= SSHMUX_FLAG_X11_FWD;
519 if (options.forward_agent)
520 flags |= SSHMUX_FLAG_AGENT_FWD;
521
522 signal(SIGPIPE, SIG_IGN);
523
524 buffer_init(&m);
525
526 /* Send our command to server */
527 buffer_put_int(&m, muxclient_command);
528 buffer_put_int(&m, flags);
529 if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
530 fatal("%s: msg_send", __func__);
531 buffer_clear(&m);
532
533 /* Get authorisation status and PID of controlee */
534 if (ssh_msg_recv(sock, &m) == -1)
535 fatal("%s: msg_recv", __func__);
536 if (buffer_get_char(&m) != SSHMUX_VER)
537 fatal("%s: wrong version", __func__);
538 if (buffer_get_int(&m) != 1)
539 fatal("Connection to master denied");
540 muxserver_pid = buffer_get_int(&m);
541
542 buffer_clear(&m);
543
544 switch (muxclient_command) {
545 case SSHMUX_COMMAND_ALIVE_CHECK:
546 fprintf(stderr, "Master running (pid=%d)\r\n",
547 muxserver_pid);
548 exit(0);
549 case SSHMUX_COMMAND_TERMINATE:
550 fprintf(stderr, "Exit request sent.\r\n");
551 exit(0);
552 case SSHMUX_COMMAND_OPEN:
553 /* continue below */
554 break;
555 default:
556 fatal("silly muxclient_command %d", muxclient_command);
557 }
558
559 /* SSHMUX_COMMAND_OPEN */
560 buffer_put_cstring(&m, term ? term : "");
561 buffer_append(&command, "\0", 1);
562 buffer_put_cstring(&m, buffer_ptr(&command));
563
564 if (options.num_send_env == 0 || environ == NULL) {
565 buffer_put_int(&m, 0);
566 } else {
567 /* Pass environment */
568 num_env = 0;
569 for (i = 0; environ[i] != NULL; i++)
570 if (env_permitted(environ[i]))
571 num_env++; /* Count */
572
573 buffer_put_int(&m, num_env);
574
575 for (i = 0; environ[i] != NULL && num_env >= 0; i++)
576 if (env_permitted(environ[i])) {
577 num_env--;
578 buffer_put_cstring(&m, environ[i]);
579 }
580 }
581
582 if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
583 fatal("%s: msg_send", __func__);
584
585 if (mm_send_fd(sock, STDIN_FILENO) == -1 ||
586 mm_send_fd(sock, STDOUT_FILENO) == -1 ||
587 mm_send_fd(sock, STDERR_FILENO) == -1)
588 fatal("%s: send fds failed", __func__);
589
590 /* Wait for reply, so master has a chance to gather ttymodes */
591 buffer_clear(&m);
592 if (ssh_msg_recv(sock, &m) == -1)
593 fatal("%s: msg_recv", __func__);
594 if (buffer_get_char(&m) != SSHMUX_VER)
595 fatal("%s: wrong version", __func__);
596 buffer_free(&m);
597
598 signal(SIGHUP, control_client_sighandler);
599 signal(SIGINT, control_client_sighandler);
600 signal(SIGTERM, control_client_sighandler);
601 signal(SIGWINCH, control_client_sigrelay);
602
603 if (tty_flag)
604 enter_raw_mode();
605
606 /*
607 * Stick around until the controlee closes the client_fd.
608 * Before it does, it is expected to write this process' exit
609 * value (one int). This process must read the value and wait for
610 * the closure of the client_fd; if this one closes early, the
611 * multiplex master will terminate early too (possibly losing data).
612 */
613 exitval[0] = 0;
614 for (i = 0; !muxclient_terminate && i < (int)sizeof(exitval);) {
615 r = read(sock, (char *)exitval + i, sizeof(exitval) - i);
616 if (r == 0) {
617 debug2("Received EOF from master");
618 break;
619 }
620 if (r == -1) {
621 if (errno == EINTR)
622 continue;
623 fatal("%s: read %s", __func__, strerror(errno));
624 }
625 i += r;
626 }
627
628 close(sock);
629 leave_raw_mode();
630 if (i > (int)sizeof(int))
631 fatal("%s: master returned too much data (%d > %lu)",
632 __func__, i, sizeof(int));
633 if (muxclient_terminate) {
634 debug2("Exiting on signal %d", muxclient_terminate);
635 exitval[0] = 255;
636 } else if (i < (int)sizeof(int)) {
637 debug2("Control master terminated unexpectedly");
638 exitval[0] = 255;
639 } else
640 debug2("Received exit status from master %d", exitval[0]);
641
642 if (tty_flag && options.log_level != SYSLOG_LEVEL_QUIET)
643 fprintf(stderr, "Shared connection to %s closed.\r\n", host);
644
645 exit(exitval[0]);
646}
diff --git a/ssh.c b/ssh.c
index cfefadef9..c944d0ad6 100644
--- a/ssh.c
+++ b/ssh.c
@@ -1,4 +1,4 @@
1/* $OpenBSD: ssh.c,v 1.311 2008/05/08 13:06:11 djm Exp $ */ 1/* $OpenBSD: ssh.c,v 1.312 2008/05/09 14:18:44 djm Exp $ */
2/* 2/*
3 * Author: Tatu Ylonen <ylo@cs.hut.fi> 3 * Author: Tatu Ylonen <ylo@cs.hut.fi>
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -49,7 +49,6 @@
49#include <sys/resource.h> 49#include <sys/resource.h>
50#include <sys/ioctl.h> 50#include <sys/ioctl.h>
51#include <sys/socket.h> 51#include <sys/socket.h>
52#include <sys/un.h>
53 52
54#include <ctype.h> 53#include <ctype.h>
55#include <errno.h> 54#include <errno.h>
@@ -99,7 +98,6 @@
99#include "sshpty.h" 98#include "sshpty.h"
100#include "match.h" 99#include "match.h"
101#include "msg.h" 100#include "msg.h"
102#include "monitor_fdpass.h"
103#include "uidswap.h" 101#include "uidswap.h"
104#include "version.h" 102#include "version.h"
105 103
@@ -171,15 +169,9 @@ static int client_global_request_id = 0;
171/* pid of proxycommand child process */ 169/* pid of proxycommand child process */
172pid_t proxy_command_pid = 0; 170pid_t proxy_command_pid = 0;
173 171
174/* fd to control socket */ 172/* mux.c */
175int control_fd = -1; 173extern int muxserver_sock;
176 174extern u_int muxclient_command;
177/* Multiplexing control command */
178static u_int mux_command = 0;
179
180/* Only used in control client mode */
181volatile sig_atomic_t control_client_terminate = 0;
182u_int control_server_pid = 0;
183 175
184/* Prints a help message to the user. This function never returns. */ 176/* Prints a help message to the user. This function never returns. */
185 177
@@ -200,7 +192,10 @@ usage(void)
200static int ssh_session(void); 192static int ssh_session(void);
201static int ssh_session2(void); 193static int ssh_session2(void);
202static void load_public_identity_files(void); 194static void load_public_identity_files(void);
203static void control_client(const char *path); 195
196/* from muxclient.c */
197void muxclient(const char *);
198void muxserver_listen(void);
204 199
205/* 200/*
206 * Main program for the ssh client. 201 * Main program for the ssh client.
@@ -310,9 +305,9 @@ main(int ac, char **av)
310 break; 305 break;
311 case 'O': 306 case 'O':
312 if (strcmp(optarg, "check") == 0) 307 if (strcmp(optarg, "check") == 0)
313 mux_command = SSHMUX_COMMAND_ALIVE_CHECK; 308 muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
314 else if (strcmp(optarg, "exit") == 0) 309 else if (strcmp(optarg, "exit") == 0)
315 mux_command = SSHMUX_COMMAND_TERMINATE; 310 muxclient_command = SSHMUX_COMMAND_TERMINATE;
316 else 311 else
317 fatal("Invalid multiplex command."); 312 fatal("Invalid multiplex command.");
318 break; 313 break;
@@ -683,10 +678,10 @@ main(int ac, char **av)
683 "r", options.user, "l", thishost, (char *)NULL); 678 "r", options.user, "l", thishost, (char *)NULL);
684 xfree(cp); 679 xfree(cp);
685 } 680 }
686 if (mux_command != 0 && options.control_path == NULL) 681 if (muxclient_command != 0 && options.control_path == NULL)
687 fatal("No ControlPath specified for \"-O\" command"); 682 fatal("No ControlPath specified for \"-O\" command");
688 if (options.control_path != NULL) 683 if (options.control_path != NULL)
689 control_client(options.control_path); 684 muxclient(options.control_path);
690 685
691 timeout_ms = options.connection_timeout * 1000; 686 timeout_ms = options.connection_timeout * 1000;
692 687
@@ -809,7 +804,7 @@ main(int ac, char **av)
809 exit_status = compat20 ? ssh_session2() : ssh_session(); 804 exit_status = compat20 ? ssh_session2() : ssh_session();
810 packet_close(); 805 packet_close();
811 806
812 if (options.control_path != NULL && control_fd != -1) 807 if (options.control_path != NULL && muxserver_sock != -1)
813 unlink(options.control_path); 808 unlink(options.control_path);
814 809
815 /* 810 /*
@@ -1064,48 +1059,6 @@ client_global_request_reply_fwd(int type, u_int32_t seq, void *ctxt)
1064 } 1059 }
1065} 1060}
1066 1061
1067static void
1068ssh_control_listener(void)
1069{
1070 struct sockaddr_un addr;
1071 mode_t old_umask;
1072 int addr_len;
1073
1074 if (options.control_path == NULL ||
1075 options.control_master == SSHCTL_MASTER_NO)
1076 return;
1077
1078 debug("setting up multiplex master socket");
1079
1080 memset(&addr, '\0', sizeof(addr));
1081 addr.sun_family = AF_UNIX;
1082 addr_len = offsetof(struct sockaddr_un, sun_path) +
1083 strlen(options.control_path) + 1;
1084
1085 if (strlcpy(addr.sun_path, options.control_path,
1086 sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
1087 fatal("ControlPath too long");
1088
1089 if ((control_fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
1090 fatal("%s socket(): %s", __func__, strerror(errno));
1091
1092 old_umask = umask(0177);
1093 if (bind(control_fd, (struct sockaddr *)&addr, addr_len) == -1) {
1094 control_fd = -1;
1095 if (errno == EINVAL || errno == EADDRINUSE)
1096 fatal("ControlSocket %s already exists",
1097 options.control_path);
1098 else
1099 fatal("%s bind(): %s", __func__, strerror(errno));
1100 }
1101 umask(old_umask);
1102
1103 if (listen(control_fd, 64) == -1)
1104 fatal("%s listen(): %s", __func__, strerror(errno));
1105
1106 set_nonblock(control_fd);
1107}
1108
1109/* request pty/x11/agent/tcpfwd/shell for channel */ 1062/* request pty/x11/agent/tcpfwd/shell for channel */
1110static void 1063static void
1111ssh_session2_setup(int id, void *arg) 1064ssh_session2_setup(int id, void *arg)
@@ -1204,7 +1157,7 @@ ssh_session2(void)
1204 ssh_local_cmd(options.local_command); 1157 ssh_local_cmd(options.local_command);
1205 1158
1206 /* Start listening for multiplex clients */ 1159 /* Start listening for multiplex clients */
1207 ssh_control_listener(); 1160 muxserver_listen();
1208 1161
1209 /* If requested, let ssh continue in the background. */ 1162 /* If requested, let ssh continue in the background. */
1210 if (fork_after_authentication_flag) 1163 if (fork_after_authentication_flag)
@@ -1272,237 +1225,3 @@ load_public_identity_files(void)
1272 bzero(pwdir, strlen(pwdir)); 1225 bzero(pwdir, strlen(pwdir));
1273 xfree(pwdir); 1226 xfree(pwdir);
1274} 1227}
1275
1276static void
1277control_client_sighandler(int signo)
1278{
1279 control_client_terminate = signo;
1280}
1281
1282static void
1283control_client_sigrelay(int signo)
1284{
1285 int save_errno = errno;
1286
1287 if (control_server_pid > 1)
1288 kill(control_server_pid, signo);
1289
1290 errno = save_errno;
1291}
1292
1293static int
1294env_permitted(char *env)
1295{
1296 int i, ret;
1297 char name[1024], *cp;
1298
1299 if ((cp = strchr(env, '=')) == NULL || cp == env)
1300 return (0);
1301 ret = snprintf(name, sizeof(name), "%.*s", (int)(cp - env), env);
1302 if (ret <= 0 || (size_t)ret >= sizeof(name))
1303 fatal("env_permitted: name '%.100s...' too long", env);
1304
1305 for (i = 0; i < options.num_send_env; i++)
1306 if (match_pattern(name, options.send_env[i]))
1307 return (1);
1308
1309 return (0);
1310}
1311
1312static void
1313control_client(const char *path)
1314{
1315 struct sockaddr_un addr;
1316 int i, r, fd, sock, exitval[2], num_env, addr_len;
1317 Buffer m;
1318 char *term;
1319 extern char **environ;
1320 u_int flags;
1321
1322 if (mux_command == 0)
1323 mux_command = SSHMUX_COMMAND_OPEN;
1324
1325 switch (options.control_master) {
1326 case SSHCTL_MASTER_AUTO:
1327 case SSHCTL_MASTER_AUTO_ASK:
1328 debug("auto-mux: Trying existing master");
1329 /* FALLTHROUGH */
1330 case SSHCTL_MASTER_NO:
1331 break;
1332 default:
1333 return;
1334 }
1335
1336 memset(&addr, '\0', sizeof(addr));
1337 addr.sun_family = AF_UNIX;
1338 addr_len = offsetof(struct sockaddr_un, sun_path) +
1339 strlen(path) + 1;
1340
1341 if (strlcpy(addr.sun_path, path,
1342 sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
1343 fatal("ControlPath too long");
1344
1345 if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
1346 fatal("%s socket(): %s", __func__, strerror(errno));
1347
1348 if (connect(sock, (struct sockaddr *)&addr, addr_len) == -1) {
1349 if (mux_command != SSHMUX_COMMAND_OPEN) {
1350 fatal("Control socket connect(%.100s): %s", path,
1351 strerror(errno));
1352 }
1353 if (errno == ENOENT)
1354 debug("Control socket \"%.100s\" does not exist", path);
1355 else {
1356 error("Control socket connect(%.100s): %s", path,
1357 strerror(errno));
1358 }
1359 close(sock);
1360 return;
1361 }
1362
1363 if (stdin_null_flag) {
1364 if ((fd = open(_PATH_DEVNULL, O_RDONLY)) == -1)
1365 fatal("open(/dev/null): %s", strerror(errno));
1366 if (dup2(fd, STDIN_FILENO) == -1)
1367 fatal("dup2: %s", strerror(errno));
1368 if (fd > STDERR_FILENO)
1369 close(fd);
1370 }
1371
1372 term = getenv("TERM");
1373
1374 flags = 0;
1375 if (tty_flag)
1376 flags |= SSHMUX_FLAG_TTY;
1377 if (subsystem_flag)
1378 flags |= SSHMUX_FLAG_SUBSYS;
1379 if (options.forward_x11)
1380 flags |= SSHMUX_FLAG_X11_FWD;
1381 if (options.forward_agent)
1382 flags |= SSHMUX_FLAG_AGENT_FWD;
1383
1384 signal(SIGPIPE, SIG_IGN);
1385
1386 buffer_init(&m);
1387
1388 /* Send our command to server */
1389 buffer_put_int(&m, mux_command);
1390 buffer_put_int(&m, flags);
1391 if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
1392 fatal("%s: msg_send", __func__);
1393 buffer_clear(&m);
1394
1395 /* Get authorisation status and PID of controlee */
1396 if (ssh_msg_recv(sock, &m) == -1)
1397 fatal("%s: msg_recv", __func__);
1398 if (buffer_get_char(&m) != SSHMUX_VER)
1399 fatal("%s: wrong version", __func__);
1400 if (buffer_get_int(&m) != 1)
1401 fatal("Connection to master denied");
1402 control_server_pid = buffer_get_int(&m);
1403
1404 buffer_clear(&m);
1405
1406 switch (mux_command) {
1407 case SSHMUX_COMMAND_ALIVE_CHECK:
1408 fprintf(stderr, "Master running (pid=%d)\r\n",
1409 control_server_pid);
1410 exit(0);
1411 case SSHMUX_COMMAND_TERMINATE:
1412 fprintf(stderr, "Exit request sent.\r\n");
1413 exit(0);
1414 case SSHMUX_COMMAND_OPEN:
1415 /* continue below */
1416 break;
1417 default:
1418 fatal("silly mux_command %d", mux_command);
1419 }
1420
1421 /* SSHMUX_COMMAND_OPEN */
1422 buffer_put_cstring(&m, term ? term : "");
1423 buffer_append(&command, "\0", 1);
1424 buffer_put_cstring(&m, buffer_ptr(&command));
1425
1426 if (options.num_send_env == 0 || environ == NULL) {
1427 buffer_put_int(&m, 0);
1428 } else {
1429 /* Pass environment */
1430 num_env = 0;
1431 for (i = 0; environ[i] != NULL; i++)
1432 if (env_permitted(environ[i]))
1433 num_env++; /* Count */
1434
1435 buffer_put_int(&m, num_env);
1436
1437 for (i = 0; environ[i] != NULL && num_env >= 0; i++)
1438 if (env_permitted(environ[i])) {
1439 num_env--;
1440 buffer_put_cstring(&m, environ[i]);
1441 }
1442 }
1443
1444 if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
1445 fatal("%s: msg_send", __func__);
1446
1447 if (mm_send_fd(sock, STDIN_FILENO) == -1 ||
1448 mm_send_fd(sock, STDOUT_FILENO) == -1 ||
1449 mm_send_fd(sock, STDERR_FILENO) == -1)
1450 fatal("%s: send fds failed", __func__);
1451
1452 /* Wait for reply, so master has a chance to gather ttymodes */
1453 buffer_clear(&m);
1454 if (ssh_msg_recv(sock, &m) == -1)
1455 fatal("%s: msg_recv", __func__);
1456 if (buffer_get_char(&m) != SSHMUX_VER)
1457 fatal("%s: wrong version", __func__);
1458 buffer_free(&m);
1459
1460 signal(SIGHUP, control_client_sighandler);
1461 signal(SIGINT, control_client_sighandler);
1462 signal(SIGTERM, control_client_sighandler);
1463 signal(SIGWINCH, control_client_sigrelay);
1464
1465 if (tty_flag)
1466 enter_raw_mode();
1467
1468 /*
1469 * Stick around until the controlee closes the client_fd.
1470 * Before it does, it is expected to write this process' exit
1471 * value (one int). This process must read the value and wait for
1472 * the closure of the client_fd; if this one closes early, the
1473 * multiplex master will terminate early too (possibly losing data).
1474 */
1475 exitval[0] = 0;
1476 for (i = 0; !control_client_terminate && i < (int)sizeof(exitval);) {
1477 r = read(sock, (char *)exitval + i, sizeof(exitval) - i);
1478 if (r == 0) {
1479 debug2("Received EOF from master");
1480 break;
1481 }
1482 if (r == -1) {
1483 if (errno == EINTR)
1484 continue;
1485 fatal("%s: read %s", __func__, strerror(errno));
1486 }
1487 i += r;
1488 }
1489
1490 close(sock);
1491 leave_raw_mode();
1492 if (i > (int)sizeof(int))
1493 fatal("%s: master returned too much data (%d > %lu)",
1494 __func__, i, sizeof(int));
1495 if (control_client_terminate) {
1496 debug2("Exiting on signal %d", control_client_terminate);
1497 exitval[0] = 255;
1498 } else if (i < (int)sizeof(int)) {
1499 debug2("Control master terminated unexpectedly");
1500 exitval[0] = 255;
1501 } else
1502 debug2("Received exit status from master %d", exitval[0]);
1503
1504 if (tty_flag && options.log_level != SYSLOG_LEVEL_QUIET)
1505 fprintf(stderr, "Shared connection to %s closed.\r\n", host);
1506
1507 exit(exitval[0]);
1508}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-29 15:33:57 +0000