the bandwidth of long fat pipes (i.e. 100Mbps+ trans-oceanic or trans-continental links). Bandwidth-delay products up to 64MB are supported. Also add support (not compiled by default) for the None cypher. The None cypher can only be enabled on non-interactive sessions (those without a pty where -T was not used) and must be enabled in both the client and server configuration files and on the client command line. Additionally, the None cypher will only be activated after authentication is complete. To enable the None cypher you must add -DNONE_CIPHER_ENABLED to CFLAGS via the make command line or in /etc/make.conf. This code is a style(9) compliant version of these features extracted from the patches published at: http://www.psc.edu/networking/projects/hpn-ssh/ Merging this patch has been a collaboration between me and Bjoern. Reviewed by: bz Approved by: re (kib), des (maintainer)
1626 lines
45 KiB
C
1626 lines
45 KiB
C
/* $OpenBSD: ssh.c,v 1.356 2011/01/06 22:23:53 djm Exp $ */
|
|
/* $FreeBSD$ */
|
|
/*
|
|
* Author: Tatu Ylonen <ylo@cs.hut.fi>
|
|
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
|
|
* All rights reserved
|
|
* Ssh client program. This program can be used to log into a remote machine.
|
|
* The software supports strong authentication, encryption, and forwarding
|
|
* of X11, TCP/IP, and authentication connections.
|
|
*
|
|
* As far as I am concerned, the code I have written for this software
|
|
* can be used freely for any purpose. Any derived versions of this
|
|
* software must be clearly marked as such, and if the derived work is
|
|
* incompatible with the protocol description in the RFC file, it must be
|
|
* called by a name other than "ssh" or "Secure Shell".
|
|
*
|
|
* Copyright (c) 1999 Niels Provos. All rights reserved.
|
|
* Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved.
|
|
*
|
|
* Modified to work with SSL by Niels Provos <provos@citi.umich.edu>
|
|
* in Canada (German citizen).
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
|
|
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
|
|
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
|
|
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#include "includes.h"
|
|
__RCSID("$FreeBSD$");
|
|
|
|
#include <sys/types.h>
|
|
#ifdef HAVE_SYS_STAT_H
|
|
# include <sys/stat.h>
|
|
#endif
|
|
#include <sys/resource.h>
|
|
#include <sys/ioctl.h>
|
|
#include <sys/param.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/wait.h>
|
|
|
|
#include <ctype.h>
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <netdb.h>
|
|
#ifdef HAVE_PATHS_H
|
|
#include <paths.h>
|
|
#endif
|
|
#include <pwd.h>
|
|
#include <signal.h>
|
|
#include <stdarg.h>
|
|
#include <stddef.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
#include <netinet/in.h>
|
|
#include <arpa/inet.h>
|
|
|
|
#include <openssl/evp.h>
|
|
#include <openssl/err.h>
|
|
#include "openbsd-compat/openssl-compat.h"
|
|
#include "openbsd-compat/sys-queue.h"
|
|
|
|
#include "xmalloc.h"
|
|
#include "ssh.h"
|
|
#include "ssh1.h"
|
|
#include "ssh2.h"
|
|
#include "canohost.h"
|
|
#include "compat.h"
|
|
#include "cipher.h"
|
|
#include "packet.h"
|
|
#include "buffer.h"
|
|
#include "channels.h"
|
|
#include "key.h"
|
|
#include "authfd.h"
|
|
#include "authfile.h"
|
|
#include "pathnames.h"
|
|
#include "dispatch.h"
|
|
#include "clientloop.h"
|
|
#include "log.h"
|
|
#include "readconf.h"
|
|
#include "sshconnect.h"
|
|
#include "misc.h"
|
|
#include "kex.h"
|
|
#include "mac.h"
|
|
#include "sshpty.h"
|
|
#include "match.h"
|
|
#include "msg.h"
|
|
#include "uidswap.h"
|
|
#include "roaming.h"
|
|
#include "version.h"
|
|
|
|
#ifdef ENABLE_PKCS11
|
|
#include "ssh-pkcs11.h"
|
|
#endif
|
|
|
|
extern char *__progname;
|
|
|
|
/* Flag indicating whether debug mode is on. May be set on the command line. */
|
|
int debug_flag = 0;
|
|
|
|
/* Flag indicating whether a tty should be allocated */
|
|
int tty_flag = 0;
|
|
int no_tty_flag = 0;
|
|
int force_tty_flag = 0;
|
|
|
|
/* don't exec a shell */
|
|
int no_shell_flag = 0;
|
|
|
|
/*
|
|
* Flag indicating that nothing should be read from stdin. This can be set
|
|
* on the command line.
|
|
*/
|
|
int stdin_null_flag = 0;
|
|
|
|
/*
|
|
* Flag indicating that the current process should be backgrounded and
|
|
* a new slave launched in the foreground for ControlPersist.
|
|
*/
|
|
int need_controlpersist_detach = 0;
|
|
|
|
/* Copies of flags for ControlPersist foreground slave */
|
|
int ostdin_null_flag, ono_shell_flag, ono_tty_flag, otty_flag;
|
|
|
|
/*
|
|
* Flag indicating that ssh should fork after authentication. This is useful
|
|
* so that the passphrase can be entered manually, and then ssh goes to the
|
|
* background.
|
|
*/
|
|
int fork_after_authentication_flag = 0;
|
|
|
|
/* forward stdio to remote host and port */
|
|
char *stdio_forward_host = NULL;
|
|
int stdio_forward_port = 0;
|
|
|
|
/*
|
|
* General data structure for command line options and options configurable
|
|
* in configuration files. See readconf.h.
|
|
*/
|
|
Options options;
|
|
|
|
/* optional user configfile */
|
|
char *config = NULL;
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|
|
|
/*
|
|
* 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
|
|
* configuration file.
|
|
*/
|
|
char *host;
|
|
|
|
/* socket address the host resolves to */
|
|
struct sockaddr_storage hostaddr;
|
|
|
|
/* Private host keys. */
|
|
Sensitive sensitive_data;
|
|
|
|
/* Original real UID. */
|
|
uid_t original_real_uid;
|
|
uid_t original_effective_uid;
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|
|
|
/* command to be executed */
|
|
Buffer command;
|
|
|
|
/* Should we execute a command or invoke a subsystem? */
|
|
int subsystem_flag = 0;
|
|
|
|
/* # of replies received for global requests */
|
|
static int remote_forward_confirms_received = 0;
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|
|
|
/* mux.c */
|
|
extern int muxserver_sock;
|
|
extern u_int muxclient_command;
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|
|
|
/* Prints a help message to the user. This function never returns. */
|
|
|
|
static void
|
|
usage(void)
|
|
{
|
|
fprintf(stderr,
|
|
"usage: ssh [-1246AaCfgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n"
|
|
" [-D [bind_address:]port] [-e escape_char] [-F configfile]\n"
|
|
" [-I pkcs11] [-i identity_file]\n"
|
|
" [-L [bind_address:]port:host:hostport]\n"
|
|
" [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
|
|
" [-R [bind_address:]port:host:hostport] [-S ctl_path]\n"
|
|
" [-W host:port] [-w local_tun[:remote_tun]]\n"
|
|
" [user@]hostname [command]\n"
|
|
);
|
|
exit(255);
|
|
}
|
|
|
|
static int ssh_session(void);
|
|
static int ssh_session2(void);
|
|
static void load_public_identity_files(void);
|
|
static void main_sigchld_handler(int);
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|
|
|
/* from muxclient.c */
|
|
void muxclient(const char *);
|
|
void muxserver_listen(void);
|
|
|
|
/*
|
|
* Main program for the ssh client.
|
|
*/
|
|
int
|
|
main(int ac, char **av)
|
|
{
|
|
int i, r, opt, exit_status, use_syslog;
|
|
char *p, *cp, *line, *argv0, buf[MAXPATHLEN], *host_arg;
|
|
struct stat st;
|
|
struct passwd *pw;
|
|
int dummy, timeout_ms;
|
|
extern int optind, optreset;
|
|
extern char *optarg;
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|
struct servent *sp;
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|
Forward fwd;
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|
|
/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
|
|
sanitise_stdfd();
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|
|
|
__progname = ssh_get_progname(av[0]);
|
|
init_rng();
|
|
|
|
/*
|
|
* Discard other fds that are hanging around. These can cause problem
|
|
* with backgrounded ssh processes started by ControlPersist.
|
|
*/
|
|
closefrom(STDERR_FILENO + 1);
|
|
|
|
/*
|
|
* Save the original real uid. It will be needed later (uid-swapping
|
|
* may clobber the real uid).
|
|
*/
|
|
original_real_uid = getuid();
|
|
original_effective_uid = geteuid();
|
|
|
|
/*
|
|
* Use uid-swapping to give up root privileges for the duration of
|
|
* option processing. We will re-instantiate the rights when we are
|
|
* ready to create the privileged port, and will permanently drop
|
|
* them when the port has been created (actually, when the connection
|
|
* has been made, as we may need to create the port several times).
|
|
*/
|
|
PRIV_END;
|
|
|
|
#ifdef HAVE_SETRLIMIT
|
|
/* If we are installed setuid root be careful to not drop core. */
|
|
if (original_real_uid != original_effective_uid) {
|
|
struct rlimit rlim;
|
|
rlim.rlim_cur = rlim.rlim_max = 0;
|
|
if (setrlimit(RLIMIT_CORE, &rlim) < 0)
|
|
fatal("setrlimit failed: %.100s", strerror(errno));
|
|
}
|
|
#endif
|
|
/* Get user data. */
|
|
pw = getpwuid(original_real_uid);
|
|
if (!pw) {
|
|
logit("You don't exist, go away!");
|
|
exit(255);
|
|
}
|
|
/* Take a copy of the returned structure. */
|
|
pw = pwcopy(pw);
|
|
|
|
/*
|
|
* Set our umask to something reasonable, as some files are created
|
|
* with the default umask. This will make them world-readable but
|
|
* writable only by the owner, which is ok for all files for which we
|
|
* don't set the modes explicitly.
|
|
*/
|
|
umask(022);
|
|
|
|
/*
|
|
* Initialize option structure to indicate that no values have been
|
|
* set.
|
|
*/
|
|
initialize_options(&options);
|
|
|
|
/* Parse command-line arguments. */
|
|
host = NULL;
|
|
use_syslog = 0;
|
|
argv0 = av[0];
|
|
|
|
again:
|
|
while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
|
|
"ACD:F:I:KL:MNO:PR:S:TVw:W:XYy")) != -1) {
|
|
switch (opt) {
|
|
case '1':
|
|
options.protocol = SSH_PROTO_1;
|
|
break;
|
|
case '2':
|
|
options.protocol = SSH_PROTO_2;
|
|
break;
|
|
case '4':
|
|
options.address_family = AF_INET;
|
|
break;
|
|
case '6':
|
|
options.address_family = AF_INET6;
|
|
break;
|
|
case 'n':
|
|
stdin_null_flag = 1;
|
|
break;
|
|
case 'f':
|
|
fork_after_authentication_flag = 1;
|
|
stdin_null_flag = 1;
|
|
break;
|
|
case 'x':
|
|
options.forward_x11 = 0;
|
|
break;
|
|
case 'X':
|
|
options.forward_x11 = 1;
|
|
break;
|
|
case 'y':
|
|
use_syslog = 1;
|
|
break;
|
|
case 'Y':
|
|
options.forward_x11 = 1;
|
|
options.forward_x11_trusted = 1;
|
|
break;
|
|
case 'g':
|
|
options.gateway_ports = 1;
|
|
break;
|
|
case 'O':
|
|
if (stdio_forward_host != NULL)
|
|
fatal("Cannot specify multiplexing "
|
|
"command with -W");
|
|
else if (muxclient_command != 0)
|
|
fatal("Multiplexing command already specified");
|
|
if (strcmp(optarg, "check") == 0)
|
|
muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
|
|
else if (strcmp(optarg, "forward") == 0)
|
|
muxclient_command = SSHMUX_COMMAND_FORWARD;
|
|
else if (strcmp(optarg, "exit") == 0)
|
|
muxclient_command = SSHMUX_COMMAND_TERMINATE;
|
|
else
|
|
fatal("Invalid multiplex command.");
|
|
break;
|
|
case 'P': /* deprecated */
|
|
options.use_privileged_port = 0;
|
|
break;
|
|
case 'a':
|
|
options.forward_agent = 0;
|
|
break;
|
|
case 'A':
|
|
options.forward_agent = 1;
|
|
break;
|
|
case 'k':
|
|
options.gss_deleg_creds = 0;
|
|
break;
|
|
case 'K':
|
|
options.gss_authentication = 1;
|
|
options.gss_deleg_creds = 1;
|
|
break;
|
|
case 'i':
|
|
if (stat(optarg, &st) < 0) {
|
|
fprintf(stderr, "Warning: Identity file %s "
|
|
"not accessible: %s.\n", optarg,
|
|
strerror(errno));
|
|
break;
|
|
}
|
|
if (options.num_identity_files >=
|
|
SSH_MAX_IDENTITY_FILES)
|
|
fatal("Too many identity files specified "
|
|
"(max %d)", SSH_MAX_IDENTITY_FILES);
|
|
options.identity_files[options.num_identity_files++] =
|
|
xstrdup(optarg);
|
|
break;
|
|
case 'I':
|
|
#ifdef ENABLE_PKCS11
|
|
options.pkcs11_provider = xstrdup(optarg);
|
|
#else
|
|
fprintf(stderr, "no support for PKCS#11.\n");
|
|
#endif
|
|
break;
|
|
case 't':
|
|
if (tty_flag)
|
|
force_tty_flag = 1;
|
|
tty_flag = 1;
|
|
break;
|
|
case 'v':
|
|
if (debug_flag == 0) {
|
|
debug_flag = 1;
|
|
options.log_level = SYSLOG_LEVEL_DEBUG1;
|
|
} else {
|
|
if (options.log_level < SYSLOG_LEVEL_DEBUG3)
|
|
options.log_level++;
|
|
break;
|
|
}
|
|
/* FALLTHROUGH */
|
|
case 'V':
|
|
fprintf(stderr, "%s, %s\n",
|
|
SSH_RELEASE, SSLeay_version(SSLEAY_VERSION));
|
|
if (opt == 'V')
|
|
exit(0);
|
|
break;
|
|
case 'w':
|
|
if (options.tun_open == -1)
|
|
options.tun_open = SSH_TUNMODE_DEFAULT;
|
|
options.tun_local = a2tun(optarg, &options.tun_remote);
|
|
if (options.tun_local == SSH_TUNID_ERR) {
|
|
fprintf(stderr,
|
|
"Bad tun device '%s'\n", optarg);
|
|
exit(255);
|
|
}
|
|
break;
|
|
case 'W':
|
|
if (stdio_forward_host != NULL)
|
|
fatal("stdio forward already specified");
|
|
if (muxclient_command != 0)
|
|
fatal("Cannot specify stdio forward with -O");
|
|
if (parse_forward(&fwd, optarg, 1, 0)) {
|
|
stdio_forward_host = fwd.listen_host;
|
|
stdio_forward_port = fwd.listen_port;
|
|
xfree(fwd.connect_host);
|
|
} else {
|
|
fprintf(stderr,
|
|
"Bad stdio forwarding specification '%s'\n",
|
|
optarg);
|
|
exit(255);
|
|
}
|
|
no_tty_flag = 1;
|
|
no_shell_flag = 1;
|
|
options.clear_forwardings = 1;
|
|
options.exit_on_forward_failure = 1;
|
|
break;
|
|
case 'q':
|
|
options.log_level = SYSLOG_LEVEL_QUIET;
|
|
break;
|
|
case 'e':
|
|
if (optarg[0] == '^' && optarg[2] == 0 &&
|
|
(u_char) optarg[1] >= 64 &&
|
|
(u_char) optarg[1] < 128)
|
|
options.escape_char = (u_char) optarg[1] & 31;
|
|
else if (strlen(optarg) == 1)
|
|
options.escape_char = (u_char) optarg[0];
|
|
else if (strcmp(optarg, "none") == 0)
|
|
options.escape_char = SSH_ESCAPECHAR_NONE;
|
|
else {
|
|
fprintf(stderr, "Bad escape character '%s'.\n",
|
|
optarg);
|
|
exit(255);
|
|
}
|
|
break;
|
|
case 'c':
|
|
if (ciphers_valid(optarg)) {
|
|
/* SSH2 only */
|
|
options.ciphers = xstrdup(optarg);
|
|
options.cipher = SSH_CIPHER_INVALID;
|
|
} else {
|
|
/* SSH1 only */
|
|
options.cipher = cipher_number(optarg);
|
|
if (options.cipher == -1) {
|
|
fprintf(stderr,
|
|
"Unknown cipher type '%s'\n",
|
|
optarg);
|
|
exit(255);
|
|
}
|
|
if (options.cipher == SSH_CIPHER_3DES)
|
|
options.ciphers = "3des-cbc";
|
|
else if (options.cipher == SSH_CIPHER_BLOWFISH)
|
|
options.ciphers = "blowfish-cbc";
|
|
else
|
|
options.ciphers = (char *)-1;
|
|
}
|
|
break;
|
|
case 'm':
|
|
if (mac_valid(optarg))
|
|
options.macs = xstrdup(optarg);
|
|
else {
|
|
fprintf(stderr, "Unknown mac type '%s'\n",
|
|
optarg);
|
|
exit(255);
|
|
}
|
|
break;
|
|
case 'M':
|
|
if (options.control_master == SSHCTL_MASTER_YES)
|
|
options.control_master = SSHCTL_MASTER_ASK;
|
|
else
|
|
options.control_master = SSHCTL_MASTER_YES;
|
|
break;
|
|
case 'p':
|
|
options.port = a2port(optarg);
|
|
if (options.port <= 0) {
|
|
fprintf(stderr, "Bad port '%s'\n", optarg);
|
|
exit(255);
|
|
}
|
|
break;
|
|
case 'l':
|
|
options.user = optarg;
|
|
break;
|
|
|
|
case 'L':
|
|
if (parse_forward(&fwd, optarg, 0, 0))
|
|
add_local_forward(&options, &fwd);
|
|
else {
|
|
fprintf(stderr,
|
|
"Bad local forwarding specification '%s'\n",
|
|
optarg);
|
|
exit(255);
|
|
}
|
|
break;
|
|
|
|
case 'R':
|
|
if (parse_forward(&fwd, optarg, 0, 1)) {
|
|
add_remote_forward(&options, &fwd);
|
|
} else {
|
|
fprintf(stderr,
|
|
"Bad remote forwarding specification "
|
|
"'%s'\n", optarg);
|
|
exit(255);
|
|
}
|
|
break;
|
|
|
|
case 'D':
|
|
if (parse_forward(&fwd, optarg, 1, 0)) {
|
|
add_local_forward(&options, &fwd);
|
|
} else {
|
|
fprintf(stderr,
|
|
"Bad dynamic forwarding specification "
|
|
"'%s'\n", optarg);
|
|
exit(255);
|
|
}
|
|
break;
|
|
|
|
case 'C':
|
|
options.compression = 1;
|
|
break;
|
|
case 'N':
|
|
no_shell_flag = 1;
|
|
no_tty_flag = 1;
|
|
break;
|
|
case 'T':
|
|
no_tty_flag = 1;
|
|
#ifdef NONE_CIPHER_ENABLED
|
|
/*
|
|
* Ensure that the user does not try to backdoor a
|
|
* NONE cipher switch on an interactive session by
|
|
* explicitly disabling it if the user asks for a
|
|
* session without a tty.
|
|
*/
|
|
options.none_switch = 0;
|
|
#endif
|
|
break;
|
|
case 'o':
|
|
dummy = 1;
|
|
line = xstrdup(optarg);
|
|
if (process_config_line(&options, host ? host : "",
|
|
line, "command-line", 0, &dummy) != 0)
|
|
exit(255);
|
|
xfree(line);
|
|
break;
|
|
case 's':
|
|
subsystem_flag = 1;
|
|
break;
|
|
case 'S':
|
|
if (options.control_path != NULL)
|
|
free(options.control_path);
|
|
options.control_path = xstrdup(optarg);
|
|
break;
|
|
case 'b':
|
|
options.bind_address = optarg;
|
|
break;
|
|
case 'F':
|
|
config = optarg;
|
|
break;
|
|
default:
|
|
usage();
|
|
}
|
|
}
|
|
|
|
ac -= optind;
|
|
av += optind;
|
|
|
|
if (ac > 0 && !host) {
|
|
if (strrchr(*av, '@')) {
|
|
p = xstrdup(*av);
|
|
cp = strrchr(p, '@');
|
|
if (cp == NULL || cp == p)
|
|
usage();
|
|
options.user = p;
|
|
*cp = '\0';
|
|
host = ++cp;
|
|
} else
|
|
host = *av;
|
|
if (ac > 1) {
|
|
optind = optreset = 1;
|
|
goto again;
|
|
}
|
|
ac--, av++;
|
|
}
|
|
|
|
/* Check that we got a host name. */
|
|
if (!host)
|
|
usage();
|
|
|
|
OpenSSL_add_all_algorithms();
|
|
ERR_load_crypto_strings();
|
|
|
|
/* Initialize the command to execute on remote host. */
|
|
buffer_init(&command);
|
|
|
|
/*
|
|
* Save the command to execute on the remote host in a buffer. There
|
|
* is no limit on the length of the command, except by the maximum
|
|
* packet size. Also sets the tty flag if there is no command.
|
|
*/
|
|
if (!ac) {
|
|
/* No command specified - execute shell on a tty. */
|
|
tty_flag = 1;
|
|
if (subsystem_flag) {
|
|
fprintf(stderr,
|
|
"You must specify a subsystem to invoke.\n");
|
|
usage();
|
|
}
|
|
} else {
|
|
/* A command has been specified. Store it into the buffer. */
|
|
for (i = 0; i < ac; i++) {
|
|
if (i)
|
|
buffer_append(&command, " ", 1);
|
|
buffer_append(&command, av[i], strlen(av[i]));
|
|
}
|
|
}
|
|
|
|
/* Cannot fork to background if no command. */
|
|
if (fork_after_authentication_flag && buffer_len(&command) == 0 &&
|
|
!no_shell_flag)
|
|
fatal("Cannot fork into background without a command "
|
|
"to execute.");
|
|
|
|
/* Allocate a tty by default if no command specified. */
|
|
if (buffer_len(&command) == 0)
|
|
tty_flag = 1;
|
|
|
|
/* Force no tty */
|
|
if (no_tty_flag || muxclient_command != 0)
|
|
tty_flag = 0;
|
|
/* Do not allocate a tty if stdin is not a tty. */
|
|
if ((!isatty(fileno(stdin)) || stdin_null_flag) && !force_tty_flag) {
|
|
if (tty_flag)
|
|
logit("Pseudo-terminal will not be allocated because "
|
|
"stdin is not a terminal.");
|
|
tty_flag = 0;
|
|
}
|
|
|
|
/*
|
|
* Initialize "log" output. Since we are the client all output
|
|
* actually goes to stderr.
|
|
*/
|
|
log_init(argv0,
|
|
options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
|
|
SYSLOG_FACILITY_USER, !use_syslog);
|
|
|
|
/*
|
|
* Read per-user configuration file. Ignore the system wide config
|
|
* file if the user specifies a config file on the command line.
|
|
*/
|
|
if (config != NULL) {
|
|
if (!read_config_file(config, host, &options, 0))
|
|
fatal("Can't open user config file %.100s: "
|
|
"%.100s", config, strerror(errno));
|
|
} else {
|
|
r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir,
|
|
_PATH_SSH_USER_CONFFILE);
|
|
if (r > 0 && (size_t)r < sizeof(buf))
|
|
(void)read_config_file(buf, host, &options, 1);
|
|
|
|
/* Read systemwide configuration file after use config. */
|
|
(void)read_config_file(_PATH_HOST_CONFIG_FILE, host,
|
|
&options, 0);
|
|
}
|
|
|
|
/* Fill configuration defaults. */
|
|
fill_default_options(&options);
|
|
|
|
channel_set_af(options.address_family);
|
|
|
|
/* reinit */
|
|
log_init(argv0, options.log_level, SYSLOG_FACILITY_USER, !use_syslog);
|
|
|
|
seed_rng();
|
|
|
|
if (options.user == NULL)
|
|
options.user = xstrdup(pw->pw_name);
|
|
|
|
/* Get default port if port has not been set. */
|
|
if (options.port == 0) {
|
|
sp = getservbyname(SSH_SERVICE_NAME, "tcp");
|
|
options.port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT;
|
|
}
|
|
|
|
/* preserve host name given on command line for %n expansion */
|
|
host_arg = host;
|
|
if (options.hostname != NULL) {
|
|
host = percent_expand(options.hostname,
|
|
"h", host, (char *)NULL);
|
|
}
|
|
|
|
if (options.local_command != NULL) {
|
|
char thishost[NI_MAXHOST];
|
|
|
|
if (gethostname(thishost, sizeof(thishost)) == -1)
|
|
fatal("gethostname: %s", strerror(errno));
|
|
snprintf(buf, sizeof(buf), "%d", options.port);
|
|
debug3("expanding LocalCommand: %s", options.local_command);
|
|
cp = options.local_command;
|
|
options.local_command = percent_expand(cp, "d", pw->pw_dir,
|
|
"h", host, "l", thishost, "n", host_arg, "r", options.user,
|
|
"p", buf, "u", pw->pw_name, (char *)NULL);
|
|
debug3("expanded LocalCommand: %s", options.local_command);
|
|
xfree(cp);
|
|
}
|
|
|
|
/* Find canonic host name. */
|
|
if (strchr(host, '.') == 0) {
|
|
struct addrinfo hints;
|
|
struct addrinfo *ai = NULL;
|
|
int errgai;
|
|
memset(&hints, 0, sizeof(hints));
|
|
hints.ai_family = options.address_family;
|
|
hints.ai_flags = AI_CANONNAME;
|
|
hints.ai_socktype = SOCK_STREAM;
|
|
errgai = getaddrinfo(host, NULL, &hints, &ai);
|
|
if (errgai == 0) {
|
|
if (ai->ai_canonname != NULL)
|
|
host = xstrdup(ai->ai_canonname);
|
|
freeaddrinfo(ai);
|
|
}
|
|
}
|
|
|
|
/* force lowercase for hostkey matching */
|
|
if (options.host_key_alias != NULL) {
|
|
for (p = options.host_key_alias; *p; p++)
|
|
if (isupper(*p))
|
|
*p = (char)tolower(*p);
|
|
}
|
|
|
|
if (options.proxy_command != NULL &&
|
|
strcmp(options.proxy_command, "none") == 0) {
|
|
xfree(options.proxy_command);
|
|
options.proxy_command = NULL;
|
|
}
|
|
if (options.control_path != NULL &&
|
|
strcmp(options.control_path, "none") == 0) {
|
|
xfree(options.control_path);
|
|
options.control_path = NULL;
|
|
}
|
|
|
|
if (options.control_path != NULL) {
|
|
char thishost[NI_MAXHOST];
|
|
|
|
if (gethostname(thishost, sizeof(thishost)) == -1)
|
|
fatal("gethostname: %s", strerror(errno));
|
|
snprintf(buf, sizeof(buf), "%d", options.port);
|
|
cp = tilde_expand_filename(options.control_path,
|
|
original_real_uid);
|
|
xfree(options.control_path);
|
|
options.control_path = percent_expand(cp, "p", buf, "h", host,
|
|
"r", options.user, "l", thishost, (char *)NULL);
|
|
xfree(cp);
|
|
}
|
|
if (muxclient_command != 0 && options.control_path == NULL)
|
|
fatal("No ControlPath specified for \"-O\" command");
|
|
if (options.control_path != NULL)
|
|
muxclient(options.control_path);
|
|
|
|
timeout_ms = options.connection_timeout * 1000;
|
|
|
|
/* Open a connection to the remote host. */
|
|
if (ssh_connect(host, &hostaddr, options.port,
|
|
options.address_family, options.connection_attempts, &timeout_ms,
|
|
options.tcp_keep_alive,
|
|
#ifdef HAVE_CYGWIN
|
|
options.use_privileged_port,
|
|
#else
|
|
original_effective_uid == 0 && options.use_privileged_port,
|
|
#endif
|
|
options.proxy_command) != 0)
|
|
exit(255);
|
|
|
|
if (timeout_ms > 0)
|
|
debug3("timeout: %d ms remain after connect", timeout_ms);
|
|
|
|
/*
|
|
* If we successfully made the connection, load the host private key
|
|
* in case we will need it later for combined rsa-rhosts
|
|
* authentication. This must be done before releasing extra
|
|
* privileges, because the file is only readable by root.
|
|
* If we cannot access the private keys, load the public keys
|
|
* instead and try to execute the ssh-keysign helper instead.
|
|
*/
|
|
sensitive_data.nkeys = 0;
|
|
sensitive_data.keys = NULL;
|
|
sensitive_data.external_keysign = 0;
|
|
if (options.rhosts_rsa_authentication ||
|
|
options.hostbased_authentication) {
|
|
sensitive_data.nkeys = 7;
|
|
sensitive_data.keys = xcalloc(sensitive_data.nkeys,
|
|
sizeof(Key));
|
|
for (i = 0; i < sensitive_data.nkeys; i++)
|
|
sensitive_data.keys[i] = NULL;
|
|
|
|
PRIV_START;
|
|
sensitive_data.keys[0] = key_load_private_type(KEY_RSA1,
|
|
_PATH_HOST_KEY_FILE, "", NULL, NULL);
|
|
sensitive_data.keys[1] = key_load_private_cert(KEY_DSA,
|
|
_PATH_HOST_DSA_KEY_FILE, "", NULL);
|
|
#ifdef OPENSSL_HAS_ECC
|
|
sensitive_data.keys[2] = key_load_private_cert(KEY_ECDSA,
|
|
_PATH_HOST_ECDSA_KEY_FILE, "", NULL);
|
|
#endif
|
|
sensitive_data.keys[3] = key_load_private_cert(KEY_RSA,
|
|
_PATH_HOST_RSA_KEY_FILE, "", NULL);
|
|
sensitive_data.keys[4] = key_load_private_type(KEY_DSA,
|
|
_PATH_HOST_DSA_KEY_FILE, "", NULL, NULL);
|
|
#ifdef OPENSSL_HAS_ECC
|
|
sensitive_data.keys[5] = key_load_private_type(KEY_ECDSA,
|
|
_PATH_HOST_ECDSA_KEY_FILE, "", NULL, NULL);
|
|
#endif
|
|
sensitive_data.keys[6] = key_load_private_type(KEY_RSA,
|
|
_PATH_HOST_RSA_KEY_FILE, "", NULL, NULL);
|
|
PRIV_END;
|
|
|
|
if (options.hostbased_authentication == 1 &&
|
|
sensitive_data.keys[0] == NULL &&
|
|
sensitive_data.keys[4] == NULL &&
|
|
sensitive_data.keys[5] == NULL &&
|
|
sensitive_data.keys[6] == NULL) {
|
|
sensitive_data.keys[1] = key_load_cert(
|
|
_PATH_HOST_DSA_KEY_FILE);
|
|
#ifdef OPENSSL_HAS_ECC
|
|
sensitive_data.keys[2] = key_load_cert(
|
|
_PATH_HOST_ECDSA_KEY_FILE);
|
|
#endif
|
|
sensitive_data.keys[3] = key_load_cert(
|
|
_PATH_HOST_RSA_KEY_FILE);
|
|
sensitive_data.keys[4] = key_load_public(
|
|
_PATH_HOST_DSA_KEY_FILE, NULL);
|
|
#ifdef OPENSSL_HAS_ECC
|
|
sensitive_data.keys[5] = key_load_public(
|
|
_PATH_HOST_ECDSA_KEY_FILE, NULL);
|
|
#endif
|
|
sensitive_data.keys[6] = key_load_public(
|
|
_PATH_HOST_RSA_KEY_FILE, NULL);
|
|
sensitive_data.external_keysign = 1;
|
|
}
|
|
}
|
|
/*
|
|
* Get rid of any extra privileges that we may have. We will no
|
|
* longer need them. Also, extra privileges could make it very hard
|
|
* to read identity files and other non-world-readable files from the
|
|
* user's home directory if it happens to be on a NFS volume where
|
|
* root is mapped to nobody.
|
|
*/
|
|
if (original_effective_uid == 0) {
|
|
PRIV_START;
|
|
permanently_set_uid(pw);
|
|
}
|
|
|
|
/*
|
|
* Now that we are back to our own permissions, create ~/.ssh
|
|
* directory if it doesn't already exist.
|
|
*/
|
|
r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir,
|
|
strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
|
|
if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0) {
|
|
#ifdef WITH_SELINUX
|
|
ssh_selinux_setfscreatecon(buf);
|
|
#endif
|
|
if (mkdir(buf, 0700) < 0)
|
|
error("Could not create directory '%.200s'.", buf);
|
|
#ifdef WITH_SELINUX
|
|
ssh_selinux_setfscreatecon(NULL);
|
|
#endif
|
|
}
|
|
/* load options.identity_files */
|
|
load_public_identity_files();
|
|
|
|
/* Expand ~ in known host file names. */
|
|
/* XXX mem-leaks: */
|
|
options.system_hostfile =
|
|
tilde_expand_filename(options.system_hostfile, original_real_uid);
|
|
options.user_hostfile =
|
|
tilde_expand_filename(options.user_hostfile, original_real_uid);
|
|
options.system_hostfile2 =
|
|
tilde_expand_filename(options.system_hostfile2, original_real_uid);
|
|
options.user_hostfile2 =
|
|
tilde_expand_filename(options.user_hostfile2, original_real_uid);
|
|
|
|
signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
|
|
signal(SIGCHLD, main_sigchld_handler);
|
|
|
|
/* Log into the remote system. Never returns if the login fails. */
|
|
ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr,
|
|
options.port, pw, timeout_ms);
|
|
|
|
if (packet_connection_is_on_socket()) {
|
|
verbose("Authenticated to %s ([%s]:%d).", host,
|
|
get_remote_ipaddr(), get_remote_port());
|
|
} else {
|
|
verbose("Authenticated to %s (via proxy).", host);
|
|
}
|
|
|
|
/* We no longer need the private host keys. Clear them now. */
|
|
if (sensitive_data.nkeys != 0) {
|
|
for (i = 0; i < sensitive_data.nkeys; i++) {
|
|
if (sensitive_data.keys[i] != NULL) {
|
|
/* Destroys contents safely */
|
|
debug3("clear hostkey %d", i);
|
|
key_free(sensitive_data.keys[i]);
|
|
sensitive_data.keys[i] = NULL;
|
|
}
|
|
}
|
|
xfree(sensitive_data.keys);
|
|
}
|
|
for (i = 0; i < options.num_identity_files; i++) {
|
|
if (options.identity_files[i]) {
|
|
xfree(options.identity_files[i]);
|
|
options.identity_files[i] = NULL;
|
|
}
|
|
if (options.identity_keys[i]) {
|
|
key_free(options.identity_keys[i]);
|
|
options.identity_keys[i] = NULL;
|
|
}
|
|
}
|
|
|
|
exit_status = compat20 ? ssh_session2() : ssh_session();
|
|
packet_close();
|
|
|
|
if (options.control_path != NULL && muxserver_sock != -1)
|
|
unlink(options.control_path);
|
|
|
|
/* Kill ProxyCommand if it is running. */
|
|
ssh_kill_proxy_command();
|
|
|
|
return exit_status;
|
|
}
|
|
|
|
static void
|
|
control_persist_detach(void)
|
|
{
|
|
pid_t pid;
|
|
int devnull;
|
|
|
|
debug("%s: backgrounding master process", __func__);
|
|
|
|
/*
|
|
* master (current process) into the background, and make the
|
|
* foreground process a client of the backgrounded master.
|
|
*/
|
|
switch ((pid = fork())) {
|
|
case -1:
|
|
fatal("%s: fork: %s", __func__, strerror(errno));
|
|
case 0:
|
|
/* Child: master process continues mainloop */
|
|
break;
|
|
default:
|
|
/* Parent: set up mux slave to connect to backgrounded master */
|
|
debug2("%s: background process is %ld", __func__, (long)pid);
|
|
stdin_null_flag = ostdin_null_flag;
|
|
no_shell_flag = ono_shell_flag;
|
|
no_tty_flag = ono_tty_flag;
|
|
tty_flag = otty_flag;
|
|
close(muxserver_sock);
|
|
muxserver_sock = -1;
|
|
options.control_master = SSHCTL_MASTER_NO;
|
|
muxclient(options.control_path);
|
|
/* muxclient() doesn't return on success. */
|
|
fatal("Failed to connect to new control master");
|
|
}
|
|
if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
|
|
error("%s: open(\"/dev/null\"): %s", __func__,
|
|
strerror(errno));
|
|
} else {
|
|
if (dup2(devnull, STDIN_FILENO) == -1 ||
|
|
dup2(devnull, STDOUT_FILENO) == -1)
|
|
error("%s: dup2: %s", __func__, strerror(errno));
|
|
if (devnull > STDERR_FILENO)
|
|
close(devnull);
|
|
}
|
|
}
|
|
|
|
/* Do fork() after authentication. Used by "ssh -f" */
|
|
static void
|
|
fork_postauth(void)
|
|
{
|
|
if (need_controlpersist_detach)
|
|
control_persist_detach();
|
|
debug("forking to background");
|
|
fork_after_authentication_flag = 0;
|
|
if (daemon(1, 1) < 0)
|
|
fatal("daemon() failed: %.200s", strerror(errno));
|
|
}
|
|
|
|
/* Callback for remote forward global requests */
|
|
static void
|
|
ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt)
|
|
{
|
|
Forward *rfwd = (Forward *)ctxt;
|
|
|
|
/* XXX verbose() on failure? */
|
|
debug("remote forward %s for: listen %d, connect %s:%d",
|
|
type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
|
|
rfwd->listen_port, rfwd->connect_host, rfwd->connect_port);
|
|
if (type == SSH2_MSG_REQUEST_SUCCESS && rfwd->listen_port == 0) {
|
|
rfwd->allocated_port = packet_get_int();
|
|
logit("Allocated port %u for remote forward to %s:%d",
|
|
rfwd->allocated_port,
|
|
rfwd->connect_host, rfwd->connect_port);
|
|
}
|
|
|
|
if (type == SSH2_MSG_REQUEST_FAILURE) {
|
|
if (options.exit_on_forward_failure)
|
|
fatal("Error: remote port forwarding failed for "
|
|
"listen port %d", rfwd->listen_port);
|
|
else
|
|
logit("Warning: remote port forwarding failed for "
|
|
"listen port %d", rfwd->listen_port);
|
|
}
|
|
if (++remote_forward_confirms_received == options.num_remote_forwards) {
|
|
debug("All remote forwarding requests processed");
|
|
if (fork_after_authentication_flag)
|
|
fork_postauth();
|
|
}
|
|
}
|
|
|
|
static void
|
|
client_cleanup_stdio_fwd(int id, void *arg)
|
|
{
|
|
debug("stdio forwarding: done");
|
|
cleanup_exit(0);
|
|
}
|
|
|
|
static int
|
|
client_setup_stdio_fwd(const char *host_to_connect, u_short port_to_connect)
|
|
{
|
|
Channel *c;
|
|
int in, out;
|
|
|
|
debug3("client_setup_stdio_fwd %s:%d", host_to_connect,
|
|
port_to_connect);
|
|
|
|
in = dup(STDIN_FILENO);
|
|
out = dup(STDOUT_FILENO);
|
|
if (in < 0 || out < 0)
|
|
fatal("channel_connect_stdio_fwd: dup() in/out failed");
|
|
|
|
if ((c = channel_connect_stdio_fwd(host_to_connect, port_to_connect,
|
|
in, out)) == NULL)
|
|
return 0;
|
|
channel_register_cleanup(c->self, client_cleanup_stdio_fwd, 0);
|
|
return 1;
|
|
}
|
|
|
|
static void
|
|
ssh_init_forwarding(void)
|
|
{
|
|
int success = 0;
|
|
int i;
|
|
|
|
if (stdio_forward_host != NULL) {
|
|
if (!compat20) {
|
|
fatal("stdio forwarding require Protocol 2");
|
|
}
|
|
if (!client_setup_stdio_fwd(stdio_forward_host,
|
|
stdio_forward_port))
|
|
fatal("Failed to connect in stdio forward mode.");
|
|
}
|
|
|
|
/* Initiate local TCP/IP port forwardings. */
|
|
for (i = 0; i < options.num_local_forwards; i++) {
|
|
debug("Local connections to %.200s:%d forwarded to remote "
|
|
"address %.200s:%d",
|
|
(options.local_forwards[i].listen_host == NULL) ?
|
|
(options.gateway_ports ? "*" : "LOCALHOST") :
|
|
options.local_forwards[i].listen_host,
|
|
options.local_forwards[i].listen_port,
|
|
options.local_forwards[i].connect_host,
|
|
options.local_forwards[i].connect_port);
|
|
success += channel_setup_local_fwd_listener(
|
|
options.local_forwards[i].listen_host,
|
|
options.local_forwards[i].listen_port,
|
|
options.local_forwards[i].connect_host,
|
|
options.local_forwards[i].connect_port,
|
|
options.gateway_ports);
|
|
}
|
|
if (i > 0 && success != i && options.exit_on_forward_failure)
|
|
fatal("Could not request local forwarding.");
|
|
if (i > 0 && success == 0)
|
|
error("Could not request local forwarding.");
|
|
|
|
/* Initiate remote TCP/IP port forwardings. */
|
|
for (i = 0; i < options.num_remote_forwards; i++) {
|
|
debug("Remote connections from %.200s:%d forwarded to "
|
|
"local address %.200s:%d",
|
|
(options.remote_forwards[i].listen_host == NULL) ?
|
|
"LOCALHOST" : options.remote_forwards[i].listen_host,
|
|
options.remote_forwards[i].listen_port,
|
|
options.remote_forwards[i].connect_host,
|
|
options.remote_forwards[i].connect_port);
|
|
if (channel_request_remote_forwarding(
|
|
options.remote_forwards[i].listen_host,
|
|
options.remote_forwards[i].listen_port,
|
|
options.remote_forwards[i].connect_host,
|
|
options.remote_forwards[i].connect_port) < 0) {
|
|
if (options.exit_on_forward_failure)
|
|
fatal("Could not request remote forwarding.");
|
|
else
|
|
logit("Warning: Could not request remote "
|
|
"forwarding.");
|
|
}
|
|
client_register_global_confirm(ssh_confirm_remote_forward,
|
|
&options.remote_forwards[i]);
|
|
}
|
|
|
|
/* Initiate tunnel forwarding. */
|
|
if (options.tun_open != SSH_TUNMODE_NO) {
|
|
if (client_request_tun_fwd(options.tun_open,
|
|
options.tun_local, options.tun_remote) == -1) {
|
|
if (options.exit_on_forward_failure)
|
|
fatal("Could not request tunnel forwarding.");
|
|
else
|
|
error("Could not request tunnel forwarding.");
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
check_agent_present(void)
|
|
{
|
|
if (options.forward_agent) {
|
|
/* Clear agent forwarding if we don't have an agent. */
|
|
if (!ssh_agent_present())
|
|
options.forward_agent = 0;
|
|
}
|
|
}
|
|
|
|
static int
|
|
ssh_session(void)
|
|
{
|
|
int type;
|
|
int interactive = 0;
|
|
int have_tty = 0;
|
|
struct winsize ws;
|
|
char *cp;
|
|
const char *display;
|
|
|
|
/* Enable compression if requested. */
|
|
if (options.compression) {
|
|
debug("Requesting compression at level %d.",
|
|
options.compression_level);
|
|
|
|
if (options.compression_level < 1 ||
|
|
options.compression_level > 9)
|
|
fatal("Compression level must be from 1 (fast) to "
|
|
"9 (slow, best).");
|
|
|
|
/* Send the request. */
|
|
packet_start(SSH_CMSG_REQUEST_COMPRESSION);
|
|
packet_put_int(options.compression_level);
|
|
packet_send();
|
|
packet_write_wait();
|
|
type = packet_read();
|
|
if (type == SSH_SMSG_SUCCESS)
|
|
packet_start_compression(options.compression_level);
|
|
else if (type == SSH_SMSG_FAILURE)
|
|
logit("Warning: Remote host refused compression.");
|
|
else
|
|
packet_disconnect("Protocol error waiting for "
|
|
"compression response.");
|
|
}
|
|
/* Allocate a pseudo tty if appropriate. */
|
|
if (tty_flag) {
|
|
debug("Requesting pty.");
|
|
|
|
/* Start the packet. */
|
|
packet_start(SSH_CMSG_REQUEST_PTY);
|
|
|
|
/* Store TERM in the packet. There is no limit on the
|
|
length of the string. */
|
|
cp = getenv("TERM");
|
|
if (!cp)
|
|
cp = "";
|
|
packet_put_cstring(cp);
|
|
|
|
/* Store window size in the packet. */
|
|
if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
|
|
memset(&ws, 0, sizeof(ws));
|
|
packet_put_int((u_int)ws.ws_row);
|
|
packet_put_int((u_int)ws.ws_col);
|
|
packet_put_int((u_int)ws.ws_xpixel);
|
|
packet_put_int((u_int)ws.ws_ypixel);
|
|
|
|
/* Store tty modes in the packet. */
|
|
tty_make_modes(fileno(stdin), NULL);
|
|
|
|
/* Send the packet, and wait for it to leave. */
|
|
packet_send();
|
|
packet_write_wait();
|
|
|
|
/* Read response from the server. */
|
|
type = packet_read();
|
|
if (type == SSH_SMSG_SUCCESS) {
|
|
interactive = 1;
|
|
have_tty = 1;
|
|
} else if (type == SSH_SMSG_FAILURE)
|
|
logit("Warning: Remote host failed or refused to "
|
|
"allocate a pseudo tty.");
|
|
else
|
|
packet_disconnect("Protocol error waiting for pty "
|
|
"request response.");
|
|
}
|
|
/* Request X11 forwarding if enabled and DISPLAY is set. */
|
|
display = getenv("DISPLAY");
|
|
if (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,
|
|
options.forward_x11_timeout,
|
|
&proto, &data);
|
|
/* Request forwarding with authentication spoofing. */
|
|
debug("Requesting X11 forwarding with authentication "
|
|
"spoofing.");
|
|
x11_request_forwarding_with_spoofing(0, display, proto, data);
|
|
|
|
/* Read response from the server. */
|
|
type = packet_read();
|
|
if (type == SSH_SMSG_SUCCESS) {
|
|
interactive = 1;
|
|
} else if (type == SSH_SMSG_FAILURE) {
|
|
logit("Warning: Remote host denied X11 forwarding.");
|
|
} else {
|
|
packet_disconnect("Protocol error waiting for X11 "
|
|
"forwarding");
|
|
}
|
|
}
|
|
/* Tell the packet module whether this is an interactive session. */
|
|
packet_set_interactive(interactive,
|
|
options.ip_qos_interactive, options.ip_qos_bulk);
|
|
|
|
/* Request authentication agent forwarding if appropriate. */
|
|
check_agent_present();
|
|
|
|
if (options.forward_agent) {
|
|
debug("Requesting authentication agent forwarding.");
|
|
auth_request_forwarding();
|
|
|
|
/* Read response from the server. */
|
|
type = packet_read();
|
|
packet_check_eom();
|
|
if (type != SSH_SMSG_SUCCESS)
|
|
logit("Warning: Remote host denied authentication agent forwarding.");
|
|
}
|
|
|
|
/* Initiate port forwardings. */
|
|
ssh_init_forwarding();
|
|
|
|
/* Execute a local command */
|
|
if (options.local_command != NULL &&
|
|
options.permit_local_command)
|
|
ssh_local_cmd(options.local_command);
|
|
|
|
/*
|
|
* If requested and we are not interested in replies to remote
|
|
* forwarding requests, then let ssh continue in the background.
|
|
*/
|
|
if (fork_after_authentication_flag) {
|
|
if (options.exit_on_forward_failure &&
|
|
options.num_remote_forwards > 0) {
|
|
debug("deferring postauth fork until remote forward "
|
|
"confirmation received");
|
|
} else
|
|
fork_postauth();
|
|
}
|
|
|
|
/*
|
|
* If a command was specified on the command line, execute the
|
|
* command now. Otherwise request the server to start a shell.
|
|
*/
|
|
if (buffer_len(&command) > 0) {
|
|
int len = buffer_len(&command);
|
|
if (len > 900)
|
|
len = 900;
|
|
debug("Sending command: %.*s", len,
|
|
(u_char *)buffer_ptr(&command));
|
|
packet_start(SSH_CMSG_EXEC_CMD);
|
|
packet_put_string(buffer_ptr(&command), buffer_len(&command));
|
|
packet_send();
|
|
packet_write_wait();
|
|
} else {
|
|
debug("Requesting shell.");
|
|
packet_start(SSH_CMSG_EXEC_SHELL);
|
|
packet_send();
|
|
packet_write_wait();
|
|
}
|
|
|
|
/* Enter the interactive session. */
|
|
return client_loop(have_tty, tty_flag ?
|
|
options.escape_char : SSH_ESCAPECHAR_NONE, 0);
|
|
}
|
|
|
|
/* request pty/x11/agent/tcpfwd/shell for channel */
|
|
static void
|
|
ssh_session2_setup(int id, int success, void *arg)
|
|
{
|
|
extern char **environ;
|
|
const char *display;
|
|
int interactive = tty_flag;
|
|
|
|
if (!success)
|
|
return; /* No need for error message, channels code sens one */
|
|
|
|
display = getenv("DISPLAY");
|
|
if (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,
|
|
options.forward_x11_timeout, &proto, &data);
|
|
/* Request forwarding with authentication spoofing. */
|
|
debug("Requesting X11 forwarding with authentication "
|
|
"spoofing.");
|
|
x11_request_forwarding_with_spoofing(id, display, proto, data);
|
|
interactive = 1;
|
|
/* XXX wait for reply */
|
|
}
|
|
|
|
check_agent_present();
|
|
if (options.forward_agent) {
|
|
debug("Requesting authentication agent forwarding.");
|
|
channel_request_start(id, "auth-agent-req@openssh.com", 0);
|
|
packet_send();
|
|
}
|
|
|
|
client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"),
|
|
NULL, fileno(stdin), &command, environ);
|
|
}
|
|
|
|
/* open new channel for a session */
|
|
static int
|
|
ssh_session2_open(void)
|
|
{
|
|
Channel *c;
|
|
int window, packetmax, in, out, err;
|
|
|
|
if (stdin_null_flag) {
|
|
in = open(_PATH_DEVNULL, O_RDONLY);
|
|
} else {
|
|
in = dup(STDIN_FILENO);
|
|
}
|
|
out = dup(STDOUT_FILENO);
|
|
err = dup(STDERR_FILENO);
|
|
|
|
if (in < 0 || out < 0 || err < 0)
|
|
fatal("dup() in/out/err failed");
|
|
|
|
/* enable nonblocking unless tty */
|
|
if (!isatty(in))
|
|
set_nonblock(in);
|
|
if (!isatty(out))
|
|
set_nonblock(out);
|
|
if (!isatty(err))
|
|
set_nonblock(err);
|
|
|
|
/*
|
|
* We need to check to see what to do about buffer sizes here.
|
|
* - In an HPN to non-HPN connection we want to limit the window size to
|
|
* something reasonable in case the far side has the large window bug.
|
|
* - In an HPN to HPN connection we want to use the max window size but
|
|
* allow the user to override it.
|
|
* - Lastly if HPN is disabled then use the ssh standard window size.
|
|
*
|
|
* We cannot just do a getsockopt() here and set the ssh window to that
|
|
* as in case of autotuning of socket buffers the window would get stuck
|
|
* at the initial buffer size, generally less than 96k. Therefore we
|
|
* need to set the maximum ssh window size to the maximum HPN buffer
|
|
* size unless the user has set TcpRcvBufPoll to no. In that case we
|
|
* can just set the window to the minimum of HPN buffer size and TCP
|
|
* receive buffer size.
|
|
*/
|
|
if (tty_flag)
|
|
options.hpn_buffer_size = CHAN_SES_WINDOW_DEFAULT;
|
|
else
|
|
options.hpn_buffer_size = CHAN_HPN_MIN_WINDOW_DEFAULT;
|
|
|
|
if (datafellows & SSH_BUG_LARGEWINDOW) {
|
|
debug("HPN to Non-HPN Connection");
|
|
} else if (options.tcp_rcv_buf_poll <= 0) {
|
|
sock_get_rcvbuf(&options.hpn_buffer_size, 0);
|
|
debug("HPNBufferSize set to TCP RWIN: %d",
|
|
options.hpn_buffer_size);
|
|
} else if (options.tcp_rcv_buf > 0) {
|
|
sock_get_rcvbuf(&options.hpn_buffer_size,
|
|
options.tcp_rcv_buf);
|
|
debug("HPNBufferSize set to user TCPRcvBuf: %d",
|
|
options.hpn_buffer_size);
|
|
}
|
|
debug("Final hpn_buffer_size = %d", options.hpn_buffer_size);
|
|
channel_set_hpn(options.hpn_disabled, options.hpn_buffer_size);
|
|
window = options.hpn_buffer_size;
|
|
|
|
packetmax = CHAN_SES_PACKET_DEFAULT;
|
|
if (tty_flag) {
|
|
window = CHAN_SES_WINDOW_DEFAULT;
|
|
window >>= 1;
|
|
packetmax >>= 1;
|
|
}
|
|
c = channel_new(
|
|
"session", SSH_CHANNEL_OPENING, in, out, err,
|
|
window, packetmax, CHAN_EXTENDED_WRITE,
|
|
"client-session", /*nonblock*/0);
|
|
if (!options.hpn_disabled && options.tcp_rcv_buf_poll > 0) {
|
|
c->dynamic_window = 1;
|
|
debug("Enabled Dynamic Window Scaling\n");
|
|
}
|
|
debug3("ssh_session2_open: channel_new: %d", c->self);
|
|
|
|
channel_send_open(c->self);
|
|
if (!no_shell_flag)
|
|
channel_register_open_confirm(c->self,
|
|
ssh_session2_setup, NULL);
|
|
|
|
return c->self;
|
|
}
|
|
|
|
static int
|
|
ssh_session2(void)
|
|
{
|
|
int id = -1;
|
|
|
|
/* XXX should be pre-session */
|
|
ssh_init_forwarding();
|
|
|
|
/* Start listening for multiplex clients */
|
|
muxserver_listen();
|
|
|
|
/*
|
|
* If we are in control persist mode, then prepare to background
|
|
* ourselves and have a foreground client attach as a control
|
|
* slave. NB. we must save copies of the flags that we override for
|
|
* the backgrounding, since we defer attachment of the slave until
|
|
* after the connection is fully established (in particular,
|
|
* async rfwd replies have been received for ExitOnForwardFailure).
|
|
*/
|
|
if (options.control_persist && muxserver_sock != -1) {
|
|
ostdin_null_flag = stdin_null_flag;
|
|
ono_shell_flag = no_shell_flag;
|
|
ono_tty_flag = no_tty_flag;
|
|
otty_flag = tty_flag;
|
|
stdin_null_flag = 1;
|
|
no_shell_flag = 1;
|
|
no_tty_flag = 1;
|
|
tty_flag = 0;
|
|
if (!fork_after_authentication_flag)
|
|
need_controlpersist_detach = 1;
|
|
fork_after_authentication_flag = 1;
|
|
}
|
|
|
|
if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN))
|
|
id = ssh_session2_open();
|
|
|
|
/* If we don't expect to open a new session, then disallow it */
|
|
if (options.control_master == SSHCTL_MASTER_NO &&
|
|
(datafellows & SSH_NEW_OPENSSH)) {
|
|
debug("Requesting no-more-sessions@openssh.com");
|
|
packet_start(SSH2_MSG_GLOBAL_REQUEST);
|
|
packet_put_cstring("no-more-sessions@openssh.com");
|
|
packet_put_char(0);
|
|
packet_send();
|
|
}
|
|
|
|
/* Execute a local command */
|
|
if (options.local_command != NULL &&
|
|
options.permit_local_command)
|
|
ssh_local_cmd(options.local_command);
|
|
|
|
/*
|
|
* If requested and we are not interested in replies to remote
|
|
* forwarding requests, then let ssh continue in the background.
|
|
*/
|
|
if (fork_after_authentication_flag) {
|
|
if (options.exit_on_forward_failure &&
|
|
options.num_remote_forwards > 0) {
|
|
debug("deferring postauth fork until remote forward "
|
|
"confirmation received");
|
|
} else
|
|
fork_postauth();
|
|
}
|
|
|
|
if (options.use_roaming)
|
|
request_roaming();
|
|
|
|
return client_loop(tty_flag, tty_flag ?
|
|
options.escape_char : SSH_ESCAPECHAR_NONE, id);
|
|
}
|
|
|
|
static void
|
|
load_public_identity_files(void)
|
|
{
|
|
char *filename, *cp, thishost[NI_MAXHOST];
|
|
char *pwdir = NULL, *pwname = NULL;
|
|
int i = 0;
|
|
Key *public;
|
|
struct passwd *pw;
|
|
u_int n_ids;
|
|
char *identity_files[SSH_MAX_IDENTITY_FILES];
|
|
Key *identity_keys[SSH_MAX_IDENTITY_FILES];
|
|
#ifdef ENABLE_PKCS11
|
|
Key **keys;
|
|
int nkeys;
|
|
#endif /* PKCS11 */
|
|
|
|
n_ids = 0;
|
|
bzero(identity_files, sizeof(identity_files));
|
|
bzero(identity_keys, sizeof(identity_keys));
|
|
|
|
#ifdef ENABLE_PKCS11
|
|
if (options.pkcs11_provider != NULL &&
|
|
options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
|
|
(pkcs11_init(!options.batch_mode) == 0) &&
|
|
(nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL,
|
|
&keys)) > 0) {
|
|
for (i = 0; i < nkeys; i++) {
|
|
if (n_ids >= SSH_MAX_IDENTITY_FILES) {
|
|
key_free(keys[i]);
|
|
continue;
|
|
}
|
|
identity_keys[n_ids] = keys[i];
|
|
identity_files[n_ids] =
|
|
xstrdup(options.pkcs11_provider); /* XXX */
|
|
n_ids++;
|
|
}
|
|
xfree(keys);
|
|
}
|
|
#endif /* ENABLE_PKCS11 */
|
|
if ((pw = getpwuid(original_real_uid)) == NULL)
|
|
fatal("load_public_identity_files: getpwuid failed");
|
|
pwname = xstrdup(pw->pw_name);
|
|
pwdir = xstrdup(pw->pw_dir);
|
|
if (gethostname(thishost, sizeof(thishost)) == -1)
|
|
fatal("load_public_identity_files: gethostname: %s",
|
|
strerror(errno));
|
|
for (i = 0; i < options.num_identity_files; i++) {
|
|
if (n_ids >= SSH_MAX_IDENTITY_FILES) {
|
|
xfree(options.identity_files[i]);
|
|
continue;
|
|
}
|
|
cp = tilde_expand_filename(options.identity_files[i],
|
|
original_real_uid);
|
|
filename = percent_expand(cp, "d", pwdir,
|
|
"u", pwname, "l", thishost, "h", host,
|
|
"r", options.user, (char *)NULL);
|
|
xfree(cp);
|
|
public = key_load_public(filename, NULL);
|
|
debug("identity file %s type %d", filename,
|
|
public ? public->type : -1);
|
|
xfree(options.identity_files[i]);
|
|
identity_files[n_ids] = filename;
|
|
identity_keys[n_ids] = public;
|
|
|
|
if (++n_ids >= SSH_MAX_IDENTITY_FILES)
|
|
continue;
|
|
|
|
/* Try to add the certificate variant too */
|
|
xasprintf(&cp, "%s-cert", filename);
|
|
public = key_load_public(cp, NULL);
|
|
debug("identity file %s type %d", cp,
|
|
public ? public->type : -1);
|
|
if (public == NULL) {
|
|
xfree(cp);
|
|
continue;
|
|
}
|
|
if (!key_is_cert(public)) {
|
|
debug("%s: key %s type %s is not a certificate",
|
|
__func__, cp, key_type(public));
|
|
key_free(public);
|
|
xfree(cp);
|
|
continue;
|
|
}
|
|
identity_keys[n_ids] = public;
|
|
/* point to the original path, most likely the private key */
|
|
identity_files[n_ids] = xstrdup(filename);
|
|
n_ids++;
|
|
}
|
|
options.num_identity_files = n_ids;
|
|
memcpy(options.identity_files, identity_files, sizeof(identity_files));
|
|
memcpy(options.identity_keys, identity_keys, sizeof(identity_keys));
|
|
|
|
bzero(pwname, strlen(pwname));
|
|
xfree(pwname);
|
|
bzero(pwdir, strlen(pwdir));
|
|
xfree(pwdir);
|
|
}
|
|
|
|
static void
|
|
main_sigchld_handler(int sig)
|
|
{
|
|
int save_errno = errno;
|
|
pid_t pid;
|
|
int status;
|
|
|
|
while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
|
|
(pid < 0 && errno == EINTR))
|
|
;
|
|
|
|
signal(sig, main_sigchld_handler);
|
|
errno = save_errno;
|
|
}
|
|
|