зеркало из https://github.com/Azure/sonic-openssh.git
2363 строки
69 KiB
C
2363 строки
69 KiB
C
/* $OpenBSD: ssh.c,v 1.569 2021/09/20 04:02:13 dtucker Exp $ */
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/*
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* Author: Tatu Ylonen <ylo@cs.hut.fi>
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* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
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* All rights reserved
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* Ssh client program. This program can be used to log into a remote machine.
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* The software supports strong authentication, encryption, and forwarding
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* of X11, TCP/IP, and authentication connections.
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*
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* As far as I am concerned, the code I have written for this software
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* can be used freely for any purpose. Any derived versions of this
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* software must be clearly marked as such, and if the derived work is
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* incompatible with the protocol description in the RFC file, it must be
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* called by a name other than "ssh" or "Secure Shell".
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*
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* Copyright (c) 1999 Niels Provos. All rights reserved.
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* Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved.
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*
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* Modified to work with SSLeay by Niels Provos <provos@citi.umich.edu>
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* in Canada (German citizen).
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include "includes.h"
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#include <sys/types.h>
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#ifdef HAVE_SYS_STAT_H
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# include <sys/stat.h>
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#endif
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#include <sys/resource.h>
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#include <sys/ioctl.h>
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#include <sys/socket.h>
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#include <sys/wait.h>
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#include <ctype.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <netdb.h>
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#ifdef HAVE_PATHS_H
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#include <paths.h>
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#endif
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#include <pwd.h>
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#include <signal.h>
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#include <stdarg.h>
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#include <stddef.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <stdarg.h>
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#include <unistd.h>
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#include <limits.h>
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#include <locale.h>
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#include <netinet/in.h>
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#include <arpa/inet.h>
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#ifdef WITH_OPENSSL
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#include <openssl/evp.h>
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#include <openssl/err.h>
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#endif
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#include "openbsd-compat/openssl-compat.h"
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#include "openbsd-compat/sys-queue.h"
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#include "xmalloc.h"
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#include "ssh.h"
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#include "ssh2.h"
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#include "canohost.h"
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#include "compat.h"
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#include "cipher.h"
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#include "packet.h"
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#include "sshbuf.h"
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#include "channels.h"
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#include "sshkey.h"
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#include "authfd.h"
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#include "authfile.h"
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#include "pathnames.h"
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#include "dispatch.h"
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#include "clientloop.h"
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#include "log.h"
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#include "misc.h"
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#include "readconf.h"
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#include "sshconnect.h"
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#include "kex.h"
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#include "mac.h"
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#include "sshpty.h"
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#include "match.h"
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#include "msg.h"
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#include "version.h"
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#include "ssherr.h"
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#include "myproposal.h"
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#include "utf8.h"
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#ifdef ENABLE_PKCS11
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#include "ssh-pkcs11.h"
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#endif
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extern char *__progname;
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/* Saves a copy of argv for setproctitle emulation */
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#ifndef HAVE_SETPROCTITLE
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static char **saved_av;
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#endif
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/* Flag indicating whether debug mode is on. May be set on the command line. */
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int debug_flag = 0;
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/* Flag indicating whether a tty should be requested */
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int tty_flag = 0;
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/*
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* Flag indicating that the current process should be backgrounded and
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* a new mux-client launched in the foreground for ControlPersist.
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*/
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int need_controlpersist_detach = 0;
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/* Copies of flags for ControlPersist foreground mux-client */
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int ostdin_null_flag, osession_type, otty_flag, orequest_tty;
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/*
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* General data structure for command line options and options configurable
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* in configuration files. See readconf.h.
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*/
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Options options;
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/* optional user configfile */
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char *config = NULL;
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/*
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* Name of the host we are connecting to. This is the name given on the
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* command line, or the Hostname specified for the user-supplied name in a
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* configuration file.
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*/
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char *host;
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/*
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* A config can specify a path to forward, overriding SSH_AUTH_SOCK. If this is
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* not NULL, forward the socket at this path instead.
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*/
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char *forward_agent_sock_path = NULL;
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/* socket address the host resolves to */
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struct sockaddr_storage hostaddr;
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/* Private host keys. */
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Sensitive sensitive_data;
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/* command to be executed */
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struct sshbuf *command;
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/* # of replies received for global requests */
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static int forward_confirms_pending = -1;
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/* mux.c */
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extern int muxserver_sock;
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extern u_int muxclient_command;
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/* Prints a help message to the user. This function never returns. */
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static void
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usage(void)
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{
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fprintf(stderr,
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"usage: ssh [-46AaCfGgKkMNnqsTtVvXxYy] [-B bind_interface]\n"
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" [-b bind_address] [-c cipher_spec] [-D [bind_address:]port]\n"
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" [-E log_file] [-e escape_char] [-F configfile] [-I pkcs11]\n"
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" [-i identity_file] [-J [user@]host[:port]] [-L address]\n"
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" [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
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" [-Q query_option] [-R address] [-S ctl_path] [-W host:port]\n"
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" [-w local_tun[:remote_tun]] destination [command [argument ...]]\n"
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);
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exit(255);
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}
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static int ssh_session2(struct ssh *, const struct ssh_conn_info *);
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static void load_public_identity_files(const struct ssh_conn_info *);
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static void main_sigchld_handler(int);
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/* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */
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static void
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tilde_expand_paths(char **paths, u_int num_paths)
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{
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u_int i;
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char *cp;
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for (i = 0; i < num_paths; i++) {
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cp = tilde_expand_filename(paths[i], getuid());
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free(paths[i]);
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paths[i] = cp;
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}
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}
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/*
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* Expands the set of percent_expand options used by the majority of keywords
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* in the client that support percent expansion.
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* Caller must free returned string.
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*/
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static char *
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default_client_percent_expand(const char *str,
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const struct ssh_conn_info *cinfo)
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{
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return percent_expand(str,
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DEFAULT_CLIENT_PERCENT_EXPAND_ARGS(cinfo),
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(char *)NULL);
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}
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/*
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* Expands the set of percent_expand options used by the majority of keywords
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* AND perform environment variable substitution.
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* Caller must free returned string.
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*/
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static char *
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default_client_percent_dollar_expand(const char *str,
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const struct ssh_conn_info *cinfo)
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{
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char *ret;
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ret = percent_dollar_expand(str,
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DEFAULT_CLIENT_PERCENT_EXPAND_ARGS(cinfo),
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(char *)NULL);
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if (ret == NULL)
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fatal("invalid environment variable expansion");
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return ret;
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}
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/*
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* Attempt to resolve a host name / port to a set of addresses and
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* optionally return any CNAMEs encountered along the way.
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* Returns NULL on failure.
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* NB. this function must operate with a options having undefined members.
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*/
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static struct addrinfo *
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resolve_host(const char *name, int port, int logerr, char *cname, size_t clen)
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{
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char strport[NI_MAXSERV];
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struct addrinfo hints, *res;
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int gaierr;
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LogLevel loglevel = SYSLOG_LEVEL_DEBUG1;
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if (port <= 0)
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port = default_ssh_port();
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if (cname != NULL)
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*cname = '\0';
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debug3_f("lookup %s:%d", name, port);
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snprintf(strport, sizeof strport, "%d", port);
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memset(&hints, 0, sizeof(hints));
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hints.ai_family = options.address_family == -1 ?
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AF_UNSPEC : options.address_family;
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hints.ai_socktype = SOCK_STREAM;
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if (cname != NULL)
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hints.ai_flags = AI_CANONNAME;
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if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) {
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if (logerr || (gaierr != EAI_NONAME && gaierr != EAI_NODATA))
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loglevel = SYSLOG_LEVEL_ERROR;
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do_log2(loglevel, "%s: Could not resolve hostname %.100s: %s",
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__progname, name, ssh_gai_strerror(gaierr));
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return NULL;
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}
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if (cname != NULL && res->ai_canonname != NULL) {
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if (strlcpy(cname, res->ai_canonname, clen) >= clen) {
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error_f("host \"%s\" cname \"%s\" too long (max %lu)",
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name, res->ai_canonname, (u_long)clen);
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if (clen > 0)
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*cname = '\0';
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}
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}
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return res;
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}
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/* Returns non-zero if name can only be an address and not a hostname */
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static int
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is_addr_fast(const char *name)
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{
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return (strchr(name, '%') != NULL || strchr(name, ':') != NULL ||
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strspn(name, "0123456789.") == strlen(name));
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}
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/* Returns non-zero if name represents a valid, single address */
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static int
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is_addr(const char *name)
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{
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char strport[NI_MAXSERV];
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struct addrinfo hints, *res;
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if (is_addr_fast(name))
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return 1;
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snprintf(strport, sizeof strport, "%u", default_ssh_port());
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memset(&hints, 0, sizeof(hints));
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hints.ai_family = options.address_family == -1 ?
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AF_UNSPEC : options.address_family;
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hints.ai_socktype = SOCK_STREAM;
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hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV;
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if (getaddrinfo(name, strport, &hints, &res) != 0)
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return 0;
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if (res == NULL || res->ai_next != NULL) {
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freeaddrinfo(res);
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return 0;
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}
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freeaddrinfo(res);
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return 1;
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}
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/*
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* Attempt to resolve a numeric host address / port to a single address.
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* Returns a canonical address string.
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* Returns NULL on failure.
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* NB. this function must operate with a options having undefined members.
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*/
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static struct addrinfo *
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resolve_addr(const char *name, int port, char *caddr, size_t clen)
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{
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char addr[NI_MAXHOST], strport[NI_MAXSERV];
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struct addrinfo hints, *res;
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int gaierr;
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if (port <= 0)
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port = default_ssh_port();
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snprintf(strport, sizeof strport, "%u", port);
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memset(&hints, 0, sizeof(hints));
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hints.ai_family = options.address_family == -1 ?
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AF_UNSPEC : options.address_family;
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hints.ai_socktype = SOCK_STREAM;
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hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV;
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if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) {
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debug2_f("could not resolve name %.100s as address: %s",
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name, ssh_gai_strerror(gaierr));
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return NULL;
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}
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if (res == NULL) {
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debug_f("getaddrinfo %.100s returned no addresses", name);
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return NULL;
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}
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if (res->ai_next != NULL) {
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debug_f("getaddrinfo %.100s returned multiple addresses", name);
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goto fail;
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}
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if ((gaierr = getnameinfo(res->ai_addr, res->ai_addrlen,
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addr, sizeof(addr), NULL, 0, NI_NUMERICHOST)) != 0) {
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debug_f("Could not format address for name %.100s: %s",
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name, ssh_gai_strerror(gaierr));
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goto fail;
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}
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if (strlcpy(caddr, addr, clen) >= clen) {
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error_f("host \"%s\" addr \"%s\" too long (max %lu)",
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name, addr, (u_long)clen);
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if (clen > 0)
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*caddr = '\0';
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fail:
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freeaddrinfo(res);
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return NULL;
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}
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return res;
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}
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/*
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* Check whether the cname is a permitted replacement for the hostname
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* and perform the replacement if it is.
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* NB. this function must operate with a options having undefined members.
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*/
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static int
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check_follow_cname(int direct, char **namep, const char *cname)
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{
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int i;
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struct allowed_cname *rule;
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if (*cname == '\0' || !config_has_permitted_cnames(&options) ||
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strcmp(*namep, cname) == 0)
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return 0;
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if (options.canonicalize_hostname == SSH_CANONICALISE_NO)
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return 0;
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/*
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* Don't attempt to canonicalize names that will be interpreted by
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* a proxy or jump host unless the user specifically requests so.
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*/
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if (!direct &&
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options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS)
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return 0;
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debug3_f("check \"%s\" CNAME \"%s\"", *namep, cname);
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for (i = 0; i < options.num_permitted_cnames; i++) {
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rule = options.permitted_cnames + i;
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if (match_pattern_list(*namep, rule->source_list, 1) != 1 ||
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match_pattern_list(cname, rule->target_list, 1) != 1)
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continue;
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verbose("Canonicalized DNS aliased hostname "
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"\"%s\" => \"%s\"", *namep, cname);
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free(*namep);
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*namep = xstrdup(cname);
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return 1;
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}
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return 0;
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}
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/*
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* Attempt to resolve the supplied hostname after applying the user's
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* canonicalization rules. Returns the address list for the host or NULL
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* if no name was found after canonicalization.
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* NB. this function must operate with a options having undefined members.
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*/
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static struct addrinfo *
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resolve_canonicalize(char **hostp, int port)
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{
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int i, direct, ndots;
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char *cp, *fullhost, newname[NI_MAXHOST];
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struct addrinfo *addrs;
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/*
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* Attempt to canonicalise addresses, regardless of
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* whether hostname canonicalisation was requested
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*/
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if ((addrs = resolve_addr(*hostp, port,
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newname, sizeof(newname))) != NULL) {
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debug2_f("hostname %.100s is address", *hostp);
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if (strcasecmp(*hostp, newname) != 0) {
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debug2_f("canonicalised address \"%s\" => \"%s\"",
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*hostp, newname);
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free(*hostp);
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*hostp = xstrdup(newname);
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}
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return addrs;
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}
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/*
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* If this looks like an address but didn't parse as one, it might
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* be an address with an invalid interface scope. Skip further
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* attempts at canonicalisation.
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*/
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if (is_addr_fast(*hostp)) {
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debug_f("hostname %.100s is an unrecognised address", *hostp);
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return NULL;
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}
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if (options.canonicalize_hostname == SSH_CANONICALISE_NO)
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return NULL;
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/*
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* Don't attempt to canonicalize names that will be interpreted by
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* a proxy unless the user specifically requests so.
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*/
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direct = option_clear_or_none(options.proxy_command) &&
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options.jump_host == NULL;
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if (!direct &&
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options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS)
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return NULL;
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/* If domain name is anchored, then resolve it now */
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if ((*hostp)[strlen(*hostp) - 1] == '.') {
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debug3_f("name is fully qualified");
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fullhost = xstrdup(*hostp);
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if ((addrs = resolve_host(fullhost, port, 0,
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newname, sizeof(newname))) != NULL)
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goto found;
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free(fullhost);
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goto notfound;
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}
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/* Don't apply canonicalization to sufficiently-qualified hostnames */
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ndots = 0;
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for (cp = *hostp; *cp != '\0'; cp++) {
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if (*cp == '.')
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ndots++;
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}
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if (ndots > options.canonicalize_max_dots) {
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debug3_f("not canonicalizing hostname \"%s\" (max dots %d)",
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*hostp, options.canonicalize_max_dots);
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return NULL;
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}
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/* Attempt each supplied suffix */
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for (i = 0; i < options.num_canonical_domains; i++) {
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if (strcasecmp(options.canonical_domains[i], "none") == 0)
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break;
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xasprintf(&fullhost, "%s.%s.", *hostp,
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options.canonical_domains[i]);
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debug3_f("attempting \"%s\" => \"%s\"", *hostp, fullhost);
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if ((addrs = resolve_host(fullhost, port, 0,
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|
newname, sizeof(newname))) == NULL) {
|
|
free(fullhost);
|
|
continue;
|
|
}
|
|
found:
|
|
/* Remove trailing '.' */
|
|
fullhost[strlen(fullhost) - 1] = '\0';
|
|
/* Follow CNAME if requested */
|
|
if (!check_follow_cname(direct, &fullhost, newname)) {
|
|
debug("Canonicalized hostname \"%s\" => \"%s\"",
|
|
*hostp, fullhost);
|
|
}
|
|
free(*hostp);
|
|
*hostp = fullhost;
|
|
return addrs;
|
|
}
|
|
notfound:
|
|
if (!options.canonicalize_fallback_local)
|
|
fatal("%s: Could not resolve host \"%s\"", __progname, *hostp);
|
|
debug2_f("host %s not found in any suffix", *hostp);
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Check the result of hostkey loading, ignoring some errors and
|
|
* fatal()ing for others.
|
|
*/
|
|
static void
|
|
check_load(int r, const char *path, const char *message)
|
|
{
|
|
switch (r) {
|
|
case 0:
|
|
break;
|
|
case SSH_ERR_INTERNAL_ERROR:
|
|
case SSH_ERR_ALLOC_FAIL:
|
|
fatal_r(r, "load %s \"%s\"", message, path);
|
|
case SSH_ERR_SYSTEM_ERROR:
|
|
/* Ignore missing files */
|
|
if (errno == ENOENT)
|
|
break;
|
|
/* FALLTHROUGH */
|
|
default:
|
|
error_r(r, "load %s \"%s\"", message, path);
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Read per-user configuration file. Ignore the system wide config
|
|
* file if the user specifies a config file on the command line.
|
|
*/
|
|
static void
|
|
process_config_files(const char *host_name, struct passwd *pw, int final_pass,
|
|
int *want_final_pass)
|
|
{
|
|
char buf[PATH_MAX];
|
|
int r;
|
|
|
|
if (config != NULL) {
|
|
if (strcasecmp(config, "none") != 0 &&
|
|
!read_config_file(config, pw, host, host_name, &options,
|
|
SSHCONF_USERCONF | (final_pass ? SSHCONF_FINAL : 0),
|
|
want_final_pass))
|
|
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, pw, host, host_name,
|
|
&options, SSHCONF_CHECKPERM | SSHCONF_USERCONF |
|
|
(final_pass ? SSHCONF_FINAL : 0), want_final_pass);
|
|
|
|
/* Read systemwide configuration file after user config. */
|
|
(void)read_config_file(_PATH_HOST_CONFIG_FILE, pw,
|
|
host, host_name, &options,
|
|
final_pass ? SSHCONF_FINAL : 0, want_final_pass);
|
|
}
|
|
}
|
|
|
|
/* Rewrite the port number in an addrinfo list of addresses */
|
|
static void
|
|
set_addrinfo_port(struct addrinfo *addrs, int port)
|
|
{
|
|
struct addrinfo *addr;
|
|
|
|
for (addr = addrs; addr != NULL; addr = addr->ai_next) {
|
|
switch (addr->ai_family) {
|
|
case AF_INET:
|
|
((struct sockaddr_in *)addr->ai_addr)->
|
|
sin_port = htons(port);
|
|
break;
|
|
case AF_INET6:
|
|
((struct sockaddr_in6 *)addr->ai_addr)->
|
|
sin6_port = htons(port);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
ssh_conn_info_free(struct ssh_conn_info *cinfo)
|
|
{
|
|
if (cinfo == NULL)
|
|
return;
|
|
free(cinfo->conn_hash_hex);
|
|
free(cinfo->shorthost);
|
|
free(cinfo->uidstr);
|
|
free(cinfo->keyalias);
|
|
free(cinfo->thishost);
|
|
free(cinfo->host_arg);
|
|
free(cinfo->portstr);
|
|
free(cinfo->remhost);
|
|
free(cinfo->remuser);
|
|
free(cinfo->homedir);
|
|
free(cinfo->locuser);
|
|
free(cinfo);
|
|
}
|
|
|
|
/*
|
|
* Main program for the ssh client.
|
|
*/
|
|
int
|
|
main(int ac, char **av)
|
|
{
|
|
struct ssh *ssh = NULL;
|
|
int i, r, opt, exit_status, use_syslog, direct, timeout_ms;
|
|
int was_addr, config_test = 0, opt_terminated = 0, want_final_pass = 0;
|
|
char *p, *cp, *line, *argv0, *logfile, *host_arg;
|
|
char cname[NI_MAXHOST], thishost[NI_MAXHOST];
|
|
struct stat st;
|
|
struct passwd *pw;
|
|
extern int optind, optreset;
|
|
extern char *optarg;
|
|
struct Forward fwd;
|
|
struct addrinfo *addrs = NULL;
|
|
size_t n, len;
|
|
u_int j;
|
|
struct ssh_conn_info *cinfo = NULL;
|
|
|
|
/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
|
|
sanitise_stdfd();
|
|
|
|
/*
|
|
* Discard other fds that are hanging around. These can cause problem
|
|
* with backgrounded ssh processes started by ControlPersist.
|
|
*/
|
|
closefrom(STDERR_FILENO + 1);
|
|
|
|
__progname = ssh_get_progname(av[0]);
|
|
|
|
#ifndef HAVE_SETPROCTITLE
|
|
/* Prepare for later setproctitle emulation */
|
|
/* Save argv so it isn't clobbered by setproctitle() emulation */
|
|
saved_av = xcalloc(ac + 1, sizeof(*saved_av));
|
|
for (i = 0; i < ac; i++)
|
|
saved_av[i] = xstrdup(av[i]);
|
|
saved_av[i] = NULL;
|
|
compat_init_setproctitle(ac, av);
|
|
av = saved_av;
|
|
#endif
|
|
|
|
seed_rng();
|
|
|
|
/* Get user data. */
|
|
pw = getpwuid(getuid());
|
|
if (!pw) {
|
|
logit("No user exists for uid %lu", (u_long)getuid());
|
|
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);
|
|
|
|
msetlocale();
|
|
|
|
/*
|
|
* Initialize option structure to indicate that no values have been
|
|
* set.
|
|
*/
|
|
initialize_options(&options);
|
|
|
|
/*
|
|
* Prepare main ssh transport/connection structures
|
|
*/
|
|
if ((ssh = ssh_alloc_session_state()) == NULL)
|
|
fatal("Couldn't allocate session state");
|
|
channel_init_channels(ssh);
|
|
|
|
/* Parse command-line arguments. */
|
|
host = NULL;
|
|
use_syslog = 0;
|
|
logfile = NULL;
|
|
argv0 = av[0];
|
|
|
|
again:
|
|
while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
|
|
"AB:CD:E:F:GI:J:KL:MNO:PQ:R:S:TVw:W:XYy")) != -1) {
|
|
switch (opt) {
|
|
case '1':
|
|
fatal("SSH protocol v.1 is no longer supported");
|
|
break;
|
|
case '2':
|
|
/* Ignored */
|
|
break;
|
|
case '4':
|
|
options.address_family = AF_INET;
|
|
break;
|
|
case '6':
|
|
options.address_family = AF_INET6;
|
|
break;
|
|
case 'n':
|
|
options.stdin_null = 1;
|
|
break;
|
|
case 'f':
|
|
options.fork_after_authentication = 1;
|
|
options.stdin_null = 1;
|
|
break;
|
|
case 'x':
|
|
options.forward_x11 = 0;
|
|
break;
|
|
case 'X':
|
|
options.forward_x11 = 1;
|
|
break;
|
|
case 'y':
|
|
use_syslog = 1;
|
|
break;
|
|
case 'E':
|
|
logfile = optarg;
|
|
break;
|
|
case 'G':
|
|
config_test = 1;
|
|
break;
|
|
case 'Y':
|
|
options.forward_x11 = 1;
|
|
options.forward_x11_trusted = 1;
|
|
break;
|
|
case 'g':
|
|
options.fwd_opts.gateway_ports = 1;
|
|
break;
|
|
case 'O':
|
|
if (options.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 if (strcmp(optarg, "stop") == 0)
|
|
muxclient_command = SSHMUX_COMMAND_STOP;
|
|
else if (strcmp(optarg, "cancel") == 0)
|
|
muxclient_command = SSHMUX_COMMAND_CANCEL_FWD;
|
|
else if (strcmp(optarg, "proxy") == 0)
|
|
muxclient_command = SSHMUX_COMMAND_PROXY;
|
|
else
|
|
fatal("Invalid multiplex command.");
|
|
break;
|
|
case 'P': /* deprecated */
|
|
break;
|
|
case 'Q':
|
|
cp = NULL;
|
|
if (strcmp(optarg, "cipher") == 0 ||
|
|
strcasecmp(optarg, "Ciphers") == 0)
|
|
cp = cipher_alg_list('\n', 0);
|
|
else if (strcmp(optarg, "cipher-auth") == 0)
|
|
cp = cipher_alg_list('\n', 1);
|
|
else if (strcmp(optarg, "mac") == 0 ||
|
|
strcasecmp(optarg, "MACs") == 0)
|
|
cp = mac_alg_list('\n');
|
|
else if (strcmp(optarg, "kex") == 0 ||
|
|
strcasecmp(optarg, "KexAlgorithms") == 0)
|
|
cp = kex_alg_list('\n');
|
|
else if (strcmp(optarg, "kex-gss") == 0)
|
|
cp = kex_gss_alg_list('\n');
|
|
else if (strcmp(optarg, "key") == 0)
|
|
cp = sshkey_alg_list(0, 0, 0, '\n');
|
|
else if (strcmp(optarg, "key-cert") == 0)
|
|
cp = sshkey_alg_list(1, 0, 0, '\n');
|
|
else if (strcmp(optarg, "key-plain") == 0)
|
|
cp = sshkey_alg_list(0, 1, 0, '\n');
|
|
else if (strcmp(optarg, "key-sig") == 0 ||
|
|
strcasecmp(optarg, "PubkeyAcceptedKeyTypes") == 0 || /* deprecated name */
|
|
strcasecmp(optarg, "PubkeyAcceptedAlgorithms") == 0 ||
|
|
strcasecmp(optarg, "HostKeyAlgorithms") == 0 ||
|
|
strcasecmp(optarg, "HostbasedKeyTypes") == 0 || /* deprecated name */
|
|
strcasecmp(optarg, "HostbasedAcceptedKeyTypes") == 0 || /* deprecated name */
|
|
strcasecmp(optarg, "HostbasedAcceptedAlgorithms") == 0)
|
|
cp = sshkey_alg_list(0, 0, 1, '\n');
|
|
else if (strcmp(optarg, "sig") == 0)
|
|
cp = sshkey_alg_list(0, 1, 1, '\n');
|
|
else if (strcmp(optarg, "protocol-version") == 0)
|
|
cp = xstrdup("2");
|
|
else if (strcmp(optarg, "compression") == 0) {
|
|
cp = xstrdup(compression_alg_list(0));
|
|
len = strlen(cp);
|
|
for (n = 0; n < len; n++)
|
|
if (cp[n] == ',')
|
|
cp[n] = '\n';
|
|
} else if (strcmp(optarg, "help") == 0) {
|
|
cp = xstrdup(
|
|
"cipher\ncipher-auth\ncompression\nkex\n"
|
|
"kex-gss\nkey\nkey-cert\nkey-plain\n"
|
|
"key-sig\nmac\nprotocol-version\nsig");
|
|
}
|
|
if (cp == NULL)
|
|
fatal("Unsupported query \"%s\"", optarg);
|
|
printf("%s\n", cp);
|
|
free(cp);
|
|
exit(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':
|
|
p = tilde_expand_filename(optarg, getuid());
|
|
if (stat(p, &st) == -1)
|
|
fprintf(stderr, "Warning: Identity file %s "
|
|
"not accessible: %s.\n", p,
|
|
strerror(errno));
|
|
else
|
|
add_identity_file(&options, NULL, p, 1);
|
|
free(p);
|
|
break;
|
|
case 'I':
|
|
#ifdef ENABLE_PKCS11
|
|
free(options.pkcs11_provider);
|
|
options.pkcs11_provider = xstrdup(optarg);
|
|
#else
|
|
fprintf(stderr, "no support for PKCS#11.\n");
|
|
#endif
|
|
break;
|
|
case 'J':
|
|
if (options.jump_host != NULL) {
|
|
fatal("Only a single -J option is permitted "
|
|
"(use commas to separate multiple "
|
|
"jump hops)");
|
|
}
|
|
if (options.proxy_command != NULL)
|
|
fatal("Cannot specify -J with ProxyCommand");
|
|
if (parse_jump(optarg, &options, 1) == -1)
|
|
fatal("Invalid -J argument");
|
|
options.proxy_command = xstrdup("none");
|
|
break;
|
|
case 't':
|
|
if (options.request_tty == REQUEST_TTY_YES)
|
|
options.request_tty = REQUEST_TTY_FORCE;
|
|
else
|
|
options.request_tty = REQUEST_TTY_YES;
|
|
break;
|
|
case 'v':
|
|
if (debug_flag == 0) {
|
|
debug_flag = 1;
|
|
options.log_level = SYSLOG_LEVEL_DEBUG1;
|
|
} else {
|
|
if (options.log_level < SYSLOG_LEVEL_DEBUG3) {
|
|
debug_flag++;
|
|
options.log_level++;
|
|
}
|
|
}
|
|
break;
|
|
case 'V':
|
|
fprintf(stderr, "%s, %s\n",
|
|
SSH_RELEASE, SSH_OPENSSL_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 (options.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)) {
|
|
options.stdio_forward_host = fwd.listen_host;
|
|
options.stdio_forward_port = fwd.listen_port;
|
|
free(fwd.connect_host);
|
|
} else {
|
|
fprintf(stderr,
|
|
"Bad stdio forwarding specification '%s'\n",
|
|
optarg);
|
|
exit(255);
|
|
}
|
|
options.request_tty = REQUEST_TTY_NO;
|
|
options.session_type = SESSION_TYPE_NONE;
|
|
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 == '+' || *optarg == '^' ?
|
|
optarg + 1 : optarg)) {
|
|
fprintf(stderr, "Unknown cipher type '%s'\n",
|
|
optarg);
|
|
exit(255);
|
|
}
|
|
free(options.ciphers);
|
|
options.ciphers = xstrdup(optarg);
|
|
break;
|
|
case 'm':
|
|
if (mac_valid(optarg)) {
|
|
free(options.macs);
|
|
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':
|
|
if (options.port == -1) {
|
|
options.port = a2port(optarg);
|
|
if (options.port <= 0) {
|
|
fprintf(stderr, "Bad port '%s'\n",
|
|
optarg);
|
|
exit(255);
|
|
}
|
|
}
|
|
break;
|
|
case 'l':
|
|
if (options.user == NULL)
|
|
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) ||
|
|
parse_forward(&fwd, optarg, 1, 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':
|
|
#ifdef WITH_ZLIB
|
|
options.compression = 1;
|
|
#else
|
|
error("Compression not supported, disabling.");
|
|
#endif
|
|
break;
|
|
case 'N':
|
|
if (options.session_type != -1 &&
|
|
options.session_type != SESSION_TYPE_NONE)
|
|
fatal("Cannot specify -N with -s/SessionType");
|
|
options.session_type = SESSION_TYPE_NONE;
|
|
options.request_tty = REQUEST_TTY_NO;
|
|
break;
|
|
case 'T':
|
|
options.request_tty = REQUEST_TTY_NO;
|
|
break;
|
|
case 'o':
|
|
line = xstrdup(optarg);
|
|
if (process_config_line(&options, pw,
|
|
host ? host : "", host ? host : "", line,
|
|
"command-line", 0, NULL, SSHCONF_USERCONF) != 0)
|
|
exit(255);
|
|
free(line);
|
|
break;
|
|
case 's':
|
|
if (options.session_type != -1 &&
|
|
options.session_type != SESSION_TYPE_SUBSYSTEM)
|
|
fatal("Cannot specify -s with -N/SessionType");
|
|
options.session_type = SESSION_TYPE_SUBSYSTEM;
|
|
break;
|
|
case 'S':
|
|
free(options.control_path);
|
|
options.control_path = xstrdup(optarg);
|
|
break;
|
|
case 'b':
|
|
options.bind_address = optarg;
|
|
break;
|
|
case 'B':
|
|
options.bind_interface = optarg;
|
|
break;
|
|
case 'F':
|
|
config = optarg;
|
|
break;
|
|
default:
|
|
usage();
|
|
}
|
|
}
|
|
|
|
if (optind > 1 && strcmp(av[optind - 1], "--") == 0)
|
|
opt_terminated = 1;
|
|
|
|
ac -= optind;
|
|
av += optind;
|
|
|
|
if (ac > 0 && !host) {
|
|
int tport;
|
|
char *tuser;
|
|
switch (parse_ssh_uri(*av, &tuser, &host, &tport)) {
|
|
case -1:
|
|
usage();
|
|
break;
|
|
case 0:
|
|
if (options.user == NULL) {
|
|
options.user = tuser;
|
|
tuser = NULL;
|
|
}
|
|
free(tuser);
|
|
if (options.port == -1 && tport != -1)
|
|
options.port = tport;
|
|
break;
|
|
default:
|
|
p = xstrdup(*av);
|
|
cp = strrchr(p, '@');
|
|
if (cp != NULL) {
|
|
if (cp == p)
|
|
usage();
|
|
if (options.user == NULL) {
|
|
options.user = p;
|
|
p = NULL;
|
|
}
|
|
*cp++ = '\0';
|
|
host = xstrdup(cp);
|
|
free(p);
|
|
} else
|
|
host = p;
|
|
break;
|
|
}
|
|
if (ac > 1 && !opt_terminated) {
|
|
optind = optreset = 1;
|
|
goto again;
|
|
}
|
|
ac--, av++;
|
|
}
|
|
|
|
/* Check that we got a host name. */
|
|
if (!host)
|
|
usage();
|
|
|
|
host_arg = xstrdup(host);
|
|
|
|
/* Initialize the command to execute on remote host. */
|
|
if ((command = sshbuf_new()) == NULL)
|
|
fatal("sshbuf_new failed");
|
|
|
|
/*
|
|
* 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. */
|
|
if (options.session_type == SESSION_TYPE_SUBSYSTEM) {
|
|
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 ((r = sshbuf_putf(command, "%s%s",
|
|
i ? " " : "", av[i])) != 0)
|
|
fatal_fr(r, "buffer error");
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Initialize "log" output. Since we are the client all output
|
|
* goes to stderr unless otherwise specified by -y or -E.
|
|
*/
|
|
if (use_syslog && logfile != NULL)
|
|
fatal("Can't specify both -y and -E");
|
|
if (logfile != NULL)
|
|
log_redirect_stderr_to(logfile);
|
|
log_init(argv0,
|
|
options.log_level == SYSLOG_LEVEL_NOT_SET ?
|
|
SYSLOG_LEVEL_INFO : options.log_level,
|
|
options.log_facility == SYSLOG_FACILITY_NOT_SET ?
|
|
SYSLOG_FACILITY_USER : options.log_facility,
|
|
!use_syslog);
|
|
|
|
if (debug_flag)
|
|
logit("%s, %s", SSH_RELEASE, SSH_OPENSSL_VERSION);
|
|
|
|
/* Parse the configuration files */
|
|
process_config_files(host_arg, pw, 0, &want_final_pass);
|
|
if (want_final_pass)
|
|
debug("configuration requests final Match pass");
|
|
|
|
/* Hostname canonicalisation needs a few options filled. */
|
|
fill_default_options_for_canonicalization(&options);
|
|
|
|
/* If the user has replaced the hostname then take it into use now */
|
|
if (options.hostname != NULL) {
|
|
/* NB. Please keep in sync with readconf.c:match_cfg_line() */
|
|
cp = percent_expand(options.hostname,
|
|
"h", host, (char *)NULL);
|
|
free(host);
|
|
host = cp;
|
|
free(options.hostname);
|
|
options.hostname = xstrdup(host);
|
|
}
|
|
|
|
/* Don't lowercase addresses, they will be explicitly canonicalised */
|
|
if ((was_addr = is_addr(host)) == 0)
|
|
lowercase(host);
|
|
|
|
/*
|
|
* Try to canonicalize if requested by configuration or the
|
|
* hostname is an address.
|
|
*/
|
|
if (options.canonicalize_hostname != SSH_CANONICALISE_NO || was_addr)
|
|
addrs = resolve_canonicalize(&host, options.port);
|
|
|
|
/*
|
|
* If CanonicalizePermittedCNAMEs have been specified but
|
|
* other canonicalization did not happen (by not being requested
|
|
* or by failing with fallback) then the hostname may still be changed
|
|
* as a result of CNAME following.
|
|
*
|
|
* Try to resolve the bare hostname name using the system resolver's
|
|
* usual search rules and then apply the CNAME follow rules.
|
|
*
|
|
* Skip the lookup if a ProxyCommand is being used unless the user
|
|
* has specifically requested canonicalisation for this case via
|
|
* CanonicalizeHostname=always
|
|
*/
|
|
direct = option_clear_or_none(options.proxy_command) &&
|
|
options.jump_host == NULL;
|
|
if (addrs == NULL && config_has_permitted_cnames(&options) && (direct ||
|
|
options.canonicalize_hostname == SSH_CANONICALISE_ALWAYS)) {
|
|
if ((addrs = resolve_host(host, options.port,
|
|
direct, cname, sizeof(cname))) == NULL) {
|
|
/* Don't fatal proxied host names not in the DNS */
|
|
if (direct)
|
|
cleanup_exit(255); /* logged in resolve_host */
|
|
} else
|
|
check_follow_cname(direct, &host, cname);
|
|
}
|
|
|
|
/*
|
|
* If canonicalisation is enabled then re-parse the configuration
|
|
* files as new stanzas may match.
|
|
*/
|
|
if (options.canonicalize_hostname != 0 && !want_final_pass) {
|
|
debug("hostname canonicalisation enabled, "
|
|
"will re-parse configuration");
|
|
want_final_pass = 1;
|
|
}
|
|
|
|
if (want_final_pass) {
|
|
debug("re-parsing configuration");
|
|
free(options.hostname);
|
|
options.hostname = xstrdup(host);
|
|
process_config_files(host_arg, pw, 1, NULL);
|
|
/*
|
|
* Address resolution happens early with canonicalisation
|
|
* enabled and the port number may have changed since, so
|
|
* reset it in address list
|
|
*/
|
|
if (addrs != NULL && options.port > 0)
|
|
set_addrinfo_port(addrs, options.port);
|
|
}
|
|
|
|
/* Fill configuration defaults. */
|
|
if (fill_default_options(&options) != 0)
|
|
cleanup_exit(255);
|
|
|
|
if (options.user == NULL)
|
|
options.user = xstrdup(pw->pw_name);
|
|
|
|
/*
|
|
* If ProxyJump option specified, then construct a ProxyCommand now.
|
|
*/
|
|
if (options.jump_host != NULL) {
|
|
char port_s[8];
|
|
const char *jumpuser = options.jump_user, *sshbin = argv0;
|
|
int port = options.port, jumpport = options.jump_port;
|
|
|
|
if (port <= 0)
|
|
port = default_ssh_port();
|
|
if (jumpport <= 0)
|
|
jumpport = default_ssh_port();
|
|
if (jumpuser == NULL)
|
|
jumpuser = options.user;
|
|
if (strcmp(options.jump_host, host) == 0 && port == jumpport &&
|
|
strcmp(options.user, jumpuser) == 0)
|
|
fatal("jumphost loop via %s", options.jump_host);
|
|
|
|
/*
|
|
* Try to use SSH indicated by argv[0], but fall back to
|
|
* "ssh" if it appears unavailable.
|
|
*/
|
|
if (strchr(argv0, '/') != NULL && access(argv0, X_OK) != 0)
|
|
sshbin = "ssh";
|
|
|
|
/* Consistency check */
|
|
if (options.proxy_command != NULL)
|
|
fatal("inconsistent options: ProxyCommand+ProxyJump");
|
|
/* Never use FD passing for ProxyJump */
|
|
options.proxy_use_fdpass = 0;
|
|
snprintf(port_s, sizeof(port_s), "%d", options.jump_port);
|
|
xasprintf(&options.proxy_command,
|
|
"%s%s%s%s%s%s%s%s%s%s%.*s -W '[%%h]:%%p' %s",
|
|
sshbin,
|
|
/* Optional "-l user" argument if jump_user set */
|
|
options.jump_user == NULL ? "" : " -l ",
|
|
options.jump_user == NULL ? "" : options.jump_user,
|
|
/* Optional "-p port" argument if jump_port set */
|
|
options.jump_port <= 0 ? "" : " -p ",
|
|
options.jump_port <= 0 ? "" : port_s,
|
|
/* Optional additional jump hosts ",..." */
|
|
options.jump_extra == NULL ? "" : " -J ",
|
|
options.jump_extra == NULL ? "" : options.jump_extra,
|
|
/* Optional "-F" argumment if -F specified */
|
|
config == NULL ? "" : " -F ",
|
|
config == NULL ? "" : config,
|
|
/* Optional "-v" arguments if -v set */
|
|
debug_flag ? " -" : "",
|
|
debug_flag, "vvv",
|
|
/* Mandatory hostname */
|
|
options.jump_host);
|
|
debug("Setting implicit ProxyCommand from ProxyJump: %s",
|
|
options.proxy_command);
|
|
}
|
|
|
|
if (options.port == 0)
|
|
options.port = default_ssh_port();
|
|
channel_set_af(ssh, options.address_family);
|
|
|
|
/* Tidy and check options */
|
|
if (options.host_key_alias != NULL)
|
|
lowercase(options.host_key_alias);
|
|
if (options.proxy_command != NULL &&
|
|
strcmp(options.proxy_command, "-") == 0 &&
|
|
options.proxy_use_fdpass)
|
|
fatal("ProxyCommand=- and ProxyUseFDPass are incompatible");
|
|
if (options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK) {
|
|
if (options.control_persist && options.control_path != NULL) {
|
|
debug("UpdateHostKeys=ask is incompatible with "
|
|
"ControlPersist; disabling");
|
|
options.update_hostkeys = 0;
|
|
} else if (sshbuf_len(command) != 0 ||
|
|
options.remote_command != NULL ||
|
|
options.request_tty == REQUEST_TTY_NO) {
|
|
debug("UpdateHostKeys=ask is incompatible with "
|
|
"remote command execution; disabling");
|
|
options.update_hostkeys = 0;
|
|
} else if (options.log_level < SYSLOG_LEVEL_INFO) {
|
|
/* no point logging anything; user won't see it */
|
|
options.update_hostkeys = 0;
|
|
}
|
|
}
|
|
if (options.connection_attempts <= 0)
|
|
fatal("Invalid number of ConnectionAttempts");
|
|
|
|
if (sshbuf_len(command) != 0 && options.remote_command != NULL)
|
|
fatal("Cannot execute command-line and remote command.");
|
|
|
|
/* Cannot fork to background if no command. */
|
|
if (options.fork_after_authentication && sshbuf_len(command) == 0 &&
|
|
options.remote_command == NULL &&
|
|
options.session_type != SESSION_TYPE_NONE)
|
|
fatal("Cannot fork into background without a command "
|
|
"to execute.");
|
|
|
|
/* reinit */
|
|
log_init(argv0, options.log_level, options.log_facility, !use_syslog);
|
|
for (j = 0; j < options.num_log_verbose; j++) {
|
|
if (strcasecmp(options.log_verbose[j], "none") == 0)
|
|
break;
|
|
log_verbose_add(options.log_verbose[j]);
|
|
}
|
|
|
|
if (options.request_tty == REQUEST_TTY_YES ||
|
|
options.request_tty == REQUEST_TTY_FORCE)
|
|
tty_flag = 1;
|
|
|
|
/* Allocate a tty by default if no command specified. */
|
|
if (sshbuf_len(command) == 0 && options.remote_command == NULL)
|
|
tty_flag = options.request_tty != REQUEST_TTY_NO;
|
|
|
|
/* Force no tty */
|
|
if (options.request_tty == REQUEST_TTY_NO ||
|
|
(muxclient_command && muxclient_command != SSHMUX_COMMAND_PROXY))
|
|
tty_flag = 0;
|
|
/* Do not allocate a tty if stdin is not a tty. */
|
|
if ((!isatty(fileno(stdin)) || options.stdin_null) &&
|
|
options.request_tty != REQUEST_TTY_FORCE) {
|
|
if (tty_flag && options.log_level != SYSLOG_LEVEL_QUIET)
|
|
logit("Pseudo-terminal will not be allocated because "
|
|
"stdin is not a terminal.");
|
|
tty_flag = 0;
|
|
}
|
|
|
|
/* Set up strings used to percent_expand() arguments */
|
|
cinfo = xcalloc(1, sizeof(*cinfo));
|
|
if (gethostname(thishost, sizeof(thishost)) == -1)
|
|
fatal("gethostname: %s", strerror(errno));
|
|
cinfo->thishost = xstrdup(thishost);
|
|
thishost[strcspn(thishost, ".")] = '\0';
|
|
cinfo->shorthost = xstrdup(thishost);
|
|
xasprintf(&cinfo->portstr, "%d", options.port);
|
|
xasprintf(&cinfo->uidstr, "%llu",
|
|
(unsigned long long)pw->pw_uid);
|
|
cinfo->keyalias = xstrdup(options.host_key_alias ?
|
|
options.host_key_alias : host_arg);
|
|
cinfo->conn_hash_hex = ssh_connection_hash(cinfo->thishost, host,
|
|
cinfo->portstr, options.user);
|
|
cinfo->host_arg = xstrdup(host_arg);
|
|
cinfo->remhost = xstrdup(host);
|
|
cinfo->remuser = xstrdup(options.user);
|
|
cinfo->homedir = xstrdup(pw->pw_dir);
|
|
cinfo->locuser = xstrdup(pw->pw_name);
|
|
|
|
/*
|
|
* Expand tokens in arguments. NB. LocalCommand is expanded later,
|
|
* after port-forwarding is set up, so it may pick up any local
|
|
* tunnel interface name allocated.
|
|
*/
|
|
if (options.remote_command != NULL) {
|
|
debug3("expanding RemoteCommand: %s", options.remote_command);
|
|
cp = options.remote_command;
|
|
options.remote_command = default_client_percent_expand(cp,
|
|
cinfo);
|
|
debug3("expanded RemoteCommand: %s", options.remote_command);
|
|
free(cp);
|
|
if ((r = sshbuf_put(command, options.remote_command,
|
|
strlen(options.remote_command))) != 0)
|
|
fatal_fr(r, "buffer error");
|
|
}
|
|
|
|
if (options.control_path != NULL) {
|
|
cp = tilde_expand_filename(options.control_path, getuid());
|
|
free(options.control_path);
|
|
options.control_path = default_client_percent_dollar_expand(cp,
|
|
cinfo);
|
|
free(cp);
|
|
}
|
|
|
|
if (options.identity_agent != NULL) {
|
|
p = tilde_expand_filename(options.identity_agent, getuid());
|
|
cp = default_client_percent_dollar_expand(p, cinfo);
|
|
free(p);
|
|
free(options.identity_agent);
|
|
options.identity_agent = cp;
|
|
}
|
|
|
|
if (options.forward_agent_sock_path != NULL) {
|
|
p = tilde_expand_filename(options.forward_agent_sock_path,
|
|
getuid());
|
|
cp = default_client_percent_dollar_expand(p, cinfo);
|
|
free(p);
|
|
free(options.forward_agent_sock_path);
|
|
options.forward_agent_sock_path = cp;
|
|
if (stat(options.forward_agent_sock_path, &st) != 0) {
|
|
error("Cannot forward agent socket path \"%s\": %s",
|
|
options.forward_agent_sock_path, strerror(errno));
|
|
if (options.exit_on_forward_failure)
|
|
cleanup_exit(255);
|
|
}
|
|
}
|
|
|
|
if (options.num_system_hostfiles > 0 &&
|
|
strcasecmp(options.system_hostfiles[0], "none") == 0) {
|
|
if (options.num_system_hostfiles > 1)
|
|
fatal("Invalid GlobalKnownHostsFiles: \"none\" "
|
|
"appears with other entries");
|
|
free(options.system_hostfiles[0]);
|
|
options.system_hostfiles[0] = NULL;
|
|
options.num_system_hostfiles = 0;
|
|
}
|
|
|
|
if (options.num_user_hostfiles > 0 &&
|
|
strcasecmp(options.user_hostfiles[0], "none") == 0) {
|
|
if (options.num_user_hostfiles > 1)
|
|
fatal("Invalid UserKnownHostsFiles: \"none\" "
|
|
"appears with other entries");
|
|
free(options.user_hostfiles[0]);
|
|
options.user_hostfiles[0] = NULL;
|
|
options.num_user_hostfiles = 0;
|
|
}
|
|
for (j = 0; j < options.num_user_hostfiles; j++) {
|
|
if (options.user_hostfiles[j] == NULL)
|
|
continue;
|
|
cp = tilde_expand_filename(options.user_hostfiles[j], getuid());
|
|
p = default_client_percent_dollar_expand(cp, cinfo);
|
|
if (strcmp(options.user_hostfiles[j], p) != 0)
|
|
debug3("expanded UserKnownHostsFile '%s' -> "
|
|
"'%s'", options.user_hostfiles[j], p);
|
|
free(options.user_hostfiles[j]);
|
|
free(cp);
|
|
options.user_hostfiles[j] = p;
|
|
}
|
|
|
|
for (i = 0; i < options.num_local_forwards; i++) {
|
|
if (options.local_forwards[i].listen_path != NULL) {
|
|
cp = options.local_forwards[i].listen_path;
|
|
p = options.local_forwards[i].listen_path =
|
|
default_client_percent_expand(cp, cinfo);
|
|
if (strcmp(cp, p) != 0)
|
|
debug3("expanded LocalForward listen path "
|
|
"'%s' -> '%s'", cp, p);
|
|
free(cp);
|
|
}
|
|
if (options.local_forwards[i].connect_path != NULL) {
|
|
cp = options.local_forwards[i].connect_path;
|
|
p = options.local_forwards[i].connect_path =
|
|
default_client_percent_expand(cp, cinfo);
|
|
if (strcmp(cp, p) != 0)
|
|
debug3("expanded LocalForward connect path "
|
|
"'%s' -> '%s'", cp, p);
|
|
free(cp);
|
|
}
|
|
}
|
|
|
|
for (i = 0; i < options.num_remote_forwards; i++) {
|
|
if (options.remote_forwards[i].listen_path != NULL) {
|
|
cp = options.remote_forwards[i].listen_path;
|
|
p = options.remote_forwards[i].listen_path =
|
|
default_client_percent_expand(cp, cinfo);
|
|
if (strcmp(cp, p) != 0)
|
|
debug3("expanded RemoteForward listen path "
|
|
"'%s' -> '%s'", cp, p);
|
|
free(cp);
|
|
}
|
|
if (options.remote_forwards[i].connect_path != NULL) {
|
|
cp = options.remote_forwards[i].connect_path;
|
|
p = options.remote_forwards[i].connect_path =
|
|
default_client_percent_expand(cp, cinfo);
|
|
if (strcmp(cp, p) != 0)
|
|
debug3("expanded RemoteForward connect path "
|
|
"'%s' -> '%s'", cp, p);
|
|
free(cp);
|
|
}
|
|
}
|
|
|
|
if (config_test) {
|
|
dump_client_config(&options, host);
|
|
exit(0);
|
|
}
|
|
|
|
/* Expand SecurityKeyProvider if it refers to an environment variable */
|
|
if (options.sk_provider != NULL && *options.sk_provider == '$' &&
|
|
strlen(options.sk_provider) > 1) {
|
|
if ((cp = getenv(options.sk_provider + 1)) == NULL) {
|
|
debug("Authenticator provider %s did not resolve; "
|
|
"disabling", options.sk_provider);
|
|
free(options.sk_provider);
|
|
options.sk_provider = NULL;
|
|
} else {
|
|
debug2("resolved SecurityKeyProvider %s => %s",
|
|
options.sk_provider, cp);
|
|
free(options.sk_provider);
|
|
options.sk_provider = xstrdup(cp);
|
|
}
|
|
}
|
|
|
|
if (muxclient_command != 0 && options.control_path == NULL)
|
|
fatal("No ControlPath specified for \"-O\" command");
|
|
if (options.control_path != NULL) {
|
|
int sock;
|
|
if ((sock = muxclient(options.control_path)) >= 0) {
|
|
ssh_packet_set_connection(ssh, sock, sock);
|
|
ssh_packet_set_mux(ssh);
|
|
goto skip_connect;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If hostname canonicalisation was not enabled, then we may not
|
|
* have yet resolved the hostname. Do so now.
|
|
*/
|
|
if (addrs == NULL && options.proxy_command == NULL) {
|
|
debug2("resolving \"%s\" port %d", host, options.port);
|
|
if ((addrs = resolve_host(host, options.port, 1,
|
|
cname, sizeof(cname))) == NULL)
|
|
cleanup_exit(255); /* resolve_host logs the error */
|
|
}
|
|
|
|
if (options.connection_timeout >= INT_MAX/1000)
|
|
timeout_ms = INT_MAX;
|
|
else
|
|
timeout_ms = options.connection_timeout * 1000;
|
|
|
|
/* Open a connection to the remote host. */
|
|
if (ssh_connect(ssh, host, host_arg, addrs, &hostaddr, options.port,
|
|
options.connection_attempts,
|
|
&timeout_ms, options.tcp_keep_alive) != 0)
|
|
exit(255);
|
|
|
|
if (addrs != NULL)
|
|
freeaddrinfo(addrs);
|
|
|
|
ssh_packet_set_timeout(ssh, options.server_alive_interval,
|
|
options.server_alive_count_max);
|
|
|
|
if (timeout_ms > 0)
|
|
debug3("timeout: %d ms remain after connect", timeout_ms);
|
|
|
|
/*
|
|
* If we successfully made the connection and we have hostbased auth
|
|
* enabled, load the public keys so we can later use the ssh-keysign
|
|
* helper to sign challenges.
|
|
*/
|
|
sensitive_data.nkeys = 0;
|
|
sensitive_data.keys = NULL;
|
|
if (options.hostbased_authentication) {
|
|
sensitive_data.nkeys = 10;
|
|
sensitive_data.keys = xcalloc(sensitive_data.nkeys,
|
|
sizeof(struct sshkey));
|
|
|
|
/* XXX check errors? */
|
|
#define L_PUBKEY(p,o) do { \
|
|
if ((o) >= sensitive_data.nkeys) \
|
|
fatal_f("pubkey out of array bounds"); \
|
|
check_load(sshkey_load_public(p, &(sensitive_data.keys[o]), NULL), \
|
|
p, "pubkey"); \
|
|
} while (0)
|
|
#define L_CERT(p,o) do { \
|
|
if ((o) >= sensitive_data.nkeys) \
|
|
fatal_f("cert out of array bounds"); \
|
|
check_load(sshkey_load_cert(p, &(sensitive_data.keys[o])), p, "cert"); \
|
|
} while (0)
|
|
|
|
if (options.hostbased_authentication == 1) {
|
|
L_CERT(_PATH_HOST_ECDSA_KEY_FILE, 0);
|
|
L_CERT(_PATH_HOST_ED25519_KEY_FILE, 1);
|
|
L_CERT(_PATH_HOST_RSA_KEY_FILE, 2);
|
|
L_CERT(_PATH_HOST_DSA_KEY_FILE, 3);
|
|
L_PUBKEY(_PATH_HOST_ECDSA_KEY_FILE, 4);
|
|
L_PUBKEY(_PATH_HOST_ED25519_KEY_FILE, 5);
|
|
L_PUBKEY(_PATH_HOST_RSA_KEY_FILE, 6);
|
|
L_PUBKEY(_PATH_HOST_DSA_KEY_FILE, 7);
|
|
L_CERT(_PATH_HOST_XMSS_KEY_FILE, 8);
|
|
L_PUBKEY(_PATH_HOST_XMSS_KEY_FILE, 9);
|
|
}
|
|
}
|
|
|
|
/* load options.identity_files */
|
|
load_public_identity_files(cinfo);
|
|
|
|
/* optionally set the SSH_AUTHSOCKET_ENV_NAME variable */
|
|
if (options.identity_agent &&
|
|
strcmp(options.identity_agent, SSH_AUTHSOCKET_ENV_NAME) != 0) {
|
|
if (strcmp(options.identity_agent, "none") == 0) {
|
|
unsetenv(SSH_AUTHSOCKET_ENV_NAME);
|
|
} else {
|
|
cp = options.identity_agent;
|
|
/* legacy (limited) format */
|
|
if (cp[0] == '$' && cp[1] != '{') {
|
|
if (!valid_env_name(cp + 1)) {
|
|
fatal("Invalid IdentityAgent "
|
|
"environment variable name %s", cp);
|
|
}
|
|
if ((p = getenv(cp + 1)) == NULL)
|
|
unsetenv(SSH_AUTHSOCKET_ENV_NAME);
|
|
else
|
|
setenv(SSH_AUTHSOCKET_ENV_NAME, p, 1);
|
|
} else {
|
|
/* identity_agent specifies a path directly */
|
|
setenv(SSH_AUTHSOCKET_ENV_NAME, cp, 1);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (options.forward_agent && options.forward_agent_sock_path != NULL) {
|
|
cp = options.forward_agent_sock_path;
|
|
if (cp[0] == '$') {
|
|
if (!valid_env_name(cp + 1)) {
|
|
fatal("Invalid ForwardAgent environment variable name %s", cp);
|
|
}
|
|
if ((p = getenv(cp + 1)) != NULL)
|
|
forward_agent_sock_path = xstrdup(p);
|
|
else
|
|
options.forward_agent = 0;
|
|
free(cp);
|
|
} else {
|
|
forward_agent_sock_path = cp;
|
|
}
|
|
}
|
|
|
|
/* Expand ~ in known host file names. */
|
|
tilde_expand_paths(options.system_hostfiles,
|
|
options.num_system_hostfiles);
|
|
tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles);
|
|
|
|
ssh_signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
|
|
ssh_signal(SIGCHLD, main_sigchld_handler);
|
|
|
|
/* Log into the remote system. Never returns if the login fails. */
|
|
ssh_login(ssh, &sensitive_data, host, (struct sockaddr *)&hostaddr,
|
|
options.port, pw, timeout_ms, cinfo);
|
|
|
|
/* 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);
|
|
sshkey_free(sensitive_data.keys[i]);
|
|
sensitive_data.keys[i] = NULL;
|
|
}
|
|
}
|
|
free(sensitive_data.keys);
|
|
}
|
|
for (i = 0; i < options.num_identity_files; i++) {
|
|
free(options.identity_files[i]);
|
|
options.identity_files[i] = NULL;
|
|
if (options.identity_keys[i]) {
|
|
sshkey_free(options.identity_keys[i]);
|
|
options.identity_keys[i] = NULL;
|
|
}
|
|
}
|
|
for (i = 0; i < options.num_certificate_files; i++) {
|
|
free(options.certificate_files[i]);
|
|
options.certificate_files[i] = NULL;
|
|
}
|
|
|
|
#ifdef ENABLE_PKCS11
|
|
(void)pkcs11_del_provider(options.pkcs11_provider);
|
|
#endif
|
|
|
|
skip_connect:
|
|
exit_status = ssh_session2(ssh, cinfo);
|
|
ssh_conn_info_free(cinfo);
|
|
ssh_packet_close(ssh);
|
|
|
|
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;
|
|
|
|
debug_f("backgrounding master process");
|
|
|
|
/*
|
|
* master (current process) into the background, and make the
|
|
* foreground process a client of the backgrounded master.
|
|
*/
|
|
switch ((pid = fork())) {
|
|
case -1:
|
|
fatal_f("fork: %s", strerror(errno));
|
|
case 0:
|
|
/* Child: master process continues mainloop */
|
|
break;
|
|
default:
|
|
/* Parent: set up mux client to connect to backgrounded master */
|
|
debug2_f("background process is %ld", (long)pid);
|
|
options.stdin_null = ostdin_null_flag;
|
|
options.request_tty = orequest_tty;
|
|
tty_flag = otty_flag;
|
|
options.session_type = osession_type;
|
|
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 (stdfd_devnull(1, 1, !(log_is_on_stderr() && debug_flag)) == -1)
|
|
error_f("stdfd_devnull failed");
|
|
daemon(1, 1);
|
|
setproctitle("%s [mux]", options.control_path);
|
|
}
|
|
|
|
/* Do fork() after authentication. Used by "ssh -f" */
|
|
static void
|
|
fork_postauth(void)
|
|
{
|
|
if (need_controlpersist_detach)
|
|
control_persist_detach();
|
|
debug("forking to background");
|
|
options.fork_after_authentication = 0;
|
|
if (daemon(1, 1) == -1)
|
|
fatal("daemon() failed: %.200s", strerror(errno));
|
|
if (stdfd_devnull(1, 1, !(log_is_on_stderr() && debug_flag)) == -1)
|
|
error_f("stdfd_devnull failed");
|
|
}
|
|
|
|
static void
|
|
forwarding_success(void)
|
|
{
|
|
if (forward_confirms_pending == -1)
|
|
return;
|
|
if (--forward_confirms_pending == 0) {
|
|
debug_f("all expected forwarding replies received");
|
|
if (options.fork_after_authentication)
|
|
fork_postauth();
|
|
} else {
|
|
debug2_f("%d expected forwarding replies remaining",
|
|
forward_confirms_pending);
|
|
}
|
|
}
|
|
|
|
/* Callback for remote forward global requests */
|
|
static void
|
|
ssh_confirm_remote_forward(struct ssh *ssh, int type, u_int32_t seq, void *ctxt)
|
|
{
|
|
struct Forward *rfwd = (struct Forward *)ctxt;
|
|
u_int port;
|
|
int r;
|
|
|
|
/* XXX verbose() on failure? */
|
|
debug("remote forward %s for: listen %s%s%d, connect %s:%d",
|
|
type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
|
|
rfwd->listen_path ? rfwd->listen_path :
|
|
rfwd->listen_host ? rfwd->listen_host : "",
|
|
(rfwd->listen_path || rfwd->listen_host) ? ":" : "",
|
|
rfwd->listen_port, rfwd->connect_path ? rfwd->connect_path :
|
|
rfwd->connect_host, rfwd->connect_port);
|
|
if (rfwd->listen_path == NULL && rfwd->listen_port == 0) {
|
|
if (type == SSH2_MSG_REQUEST_SUCCESS) {
|
|
if ((r = sshpkt_get_u32(ssh, &port)) != 0)
|
|
fatal_fr(r, "parse packet");
|
|
if (port > 65535) {
|
|
error("Invalid allocated port %u for remote "
|
|
"forward to %s:%d", port,
|
|
rfwd->connect_host, rfwd->connect_port);
|
|
/* Ensure failure processing runs below */
|
|
type = SSH2_MSG_REQUEST_FAILURE;
|
|
channel_update_permission(ssh,
|
|
rfwd->handle, -1);
|
|
} else {
|
|
rfwd->allocated_port = (int)port;
|
|
logit("Allocated port %u for remote "
|
|
"forward to %s:%d",
|
|
rfwd->allocated_port, rfwd->connect_path ?
|
|
rfwd->connect_path : rfwd->connect_host,
|
|
rfwd->connect_port);
|
|
channel_update_permission(ssh,
|
|
rfwd->handle, rfwd->allocated_port);
|
|
}
|
|
} else {
|
|
channel_update_permission(ssh, rfwd->handle, -1);
|
|
}
|
|
}
|
|
|
|
if (type == SSH2_MSG_REQUEST_FAILURE) {
|
|
if (options.exit_on_forward_failure) {
|
|
if (rfwd->listen_path != NULL)
|
|
fatal("Error: remote port forwarding failed "
|
|
"for listen path %s", rfwd->listen_path);
|
|
else
|
|
fatal("Error: remote port forwarding failed "
|
|
"for listen port %d", rfwd->listen_port);
|
|
} else {
|
|
if (rfwd->listen_path != NULL)
|
|
logit("Warning: remote port forwarding failed "
|
|
"for listen path %s", rfwd->listen_path);
|
|
else
|
|
logit("Warning: remote port forwarding failed "
|
|
"for listen port %d", rfwd->listen_port);
|
|
}
|
|
}
|
|
forwarding_success();
|
|
}
|
|
|
|
static void
|
|
client_cleanup_stdio_fwd(struct ssh *ssh, int id, void *arg)
|
|
{
|
|
debug("stdio forwarding: done");
|
|
cleanup_exit(0);
|
|
}
|
|
|
|
static void
|
|
ssh_stdio_confirm(struct ssh *ssh, int id, int success, void *arg)
|
|
{
|
|
if (!success)
|
|
fatal("stdio forwarding failed");
|
|
}
|
|
|
|
static void
|
|
ssh_tun_confirm(struct ssh *ssh, int id, int success, void *arg)
|
|
{
|
|
if (!success) {
|
|
error("Tunnel forwarding failed");
|
|
if (options.exit_on_forward_failure)
|
|
cleanup_exit(255);
|
|
}
|
|
|
|
debug_f("tunnel forward established, id=%d", id);
|
|
forwarding_success();
|
|
}
|
|
|
|
static void
|
|
ssh_init_stdio_forwarding(struct ssh *ssh)
|
|
{
|
|
Channel *c;
|
|
int in, out;
|
|
|
|
if (options.stdio_forward_host == NULL)
|
|
return;
|
|
|
|
debug3_f("%s:%d", options.stdio_forward_host,
|
|
options.stdio_forward_port);
|
|
|
|
if ((in = dup(STDIN_FILENO)) == -1 ||
|
|
(out = dup(STDOUT_FILENO)) == -1)
|
|
fatal_f("dup() in/out failed");
|
|
if ((c = channel_connect_stdio_fwd(ssh, options.stdio_forward_host,
|
|
options.stdio_forward_port, in, out,
|
|
CHANNEL_NONBLOCK_STDIO)) == NULL)
|
|
fatal_f("channel_connect_stdio_fwd failed");
|
|
channel_register_cleanup(ssh, c->self, client_cleanup_stdio_fwd, 0);
|
|
channel_register_open_confirm(ssh, c->self, ssh_stdio_confirm, NULL);
|
|
}
|
|
|
|
static void
|
|
ssh_init_forward_permissions(struct ssh *ssh, const char *what, char **opens,
|
|
u_int num_opens)
|
|
{
|
|
u_int i;
|
|
int port;
|
|
char *addr, *arg, *oarg, ch;
|
|
int where = FORWARD_LOCAL;
|
|
|
|
channel_clear_permission(ssh, FORWARD_ADM, where);
|
|
if (num_opens == 0)
|
|
return; /* permit any */
|
|
|
|
/* handle keywords: "any" / "none" */
|
|
if (num_opens == 1 && strcmp(opens[0], "any") == 0)
|
|
return;
|
|
if (num_opens == 1 && strcmp(opens[0], "none") == 0) {
|
|
channel_disable_admin(ssh, where);
|
|
return;
|
|
}
|
|
/* Otherwise treat it as a list of permitted host:port */
|
|
for (i = 0; i < num_opens; i++) {
|
|
oarg = arg = xstrdup(opens[i]);
|
|
ch = '\0';
|
|
addr = hpdelim2(&arg, &ch);
|
|
if (addr == NULL || ch == '/')
|
|
fatal_f("missing host in %s", what);
|
|
addr = cleanhostname(addr);
|
|
if (arg == NULL || ((port = permitopen_port(arg)) < 0))
|
|
fatal_f("bad port number in %s", what);
|
|
/* Send it to channels layer */
|
|
channel_add_permission(ssh, FORWARD_ADM,
|
|
where, addr, port);
|
|
free(oarg);
|
|
}
|
|
}
|
|
|
|
static void
|
|
ssh_init_forwarding(struct ssh *ssh, char **ifname)
|
|
{
|
|
int success = 0;
|
|
int i;
|
|
|
|
ssh_init_forward_permissions(ssh, "permitremoteopen",
|
|
options.permitted_remote_opens,
|
|
options.num_permitted_remote_opens);
|
|
|
|
if (options.exit_on_forward_failure)
|
|
forward_confirms_pending = 0; /* track pending requests */
|
|
/* 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_path != NULL) ?
|
|
options.local_forwards[i].listen_path :
|
|
(options.local_forwards[i].listen_host == NULL) ?
|
|
(options.fwd_opts.gateway_ports ? "*" : "LOCALHOST") :
|
|
options.local_forwards[i].listen_host,
|
|
options.local_forwards[i].listen_port,
|
|
(options.local_forwards[i].connect_path != NULL) ?
|
|
options.local_forwards[i].connect_path :
|
|
options.local_forwards[i].connect_host,
|
|
options.local_forwards[i].connect_port);
|
|
success += channel_setup_local_fwd_listener(ssh,
|
|
&options.local_forwards[i], &options.fwd_opts);
|
|
}
|
|
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_path != NULL) ?
|
|
options.remote_forwards[i].listen_path :
|
|
(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_path != NULL) ?
|
|
options.remote_forwards[i].connect_path :
|
|
options.remote_forwards[i].connect_host,
|
|
options.remote_forwards[i].connect_port);
|
|
if ((options.remote_forwards[i].handle =
|
|
channel_request_remote_forwarding(ssh,
|
|
&options.remote_forwards[i])) >= 0) {
|
|
client_register_global_confirm(
|
|
ssh_confirm_remote_forward,
|
|
&options.remote_forwards[i]);
|
|
forward_confirms_pending++;
|
|
} else if (options.exit_on_forward_failure)
|
|
fatal("Could not request remote forwarding.");
|
|
else
|
|
logit("Warning: Could not request remote forwarding.");
|
|
}
|
|
|
|
/* Initiate tunnel forwarding. */
|
|
if (options.tun_open != SSH_TUNMODE_NO) {
|
|
if ((*ifname = client_request_tun_fwd(ssh,
|
|
options.tun_open, options.tun_local,
|
|
options.tun_remote, ssh_tun_confirm, NULL)) != NULL)
|
|
forward_confirms_pending++;
|
|
else if (options.exit_on_forward_failure)
|
|
fatal("Could not request tunnel forwarding.");
|
|
else
|
|
error("Could not request tunnel forwarding.");
|
|
}
|
|
if (forward_confirms_pending > 0) {
|
|
debug_f("expecting replies for %d forwards",
|
|
forward_confirms_pending);
|
|
}
|
|
}
|
|
|
|
static void
|
|
check_agent_present(void)
|
|
{
|
|
int r;
|
|
|
|
if (options.forward_agent) {
|
|
/* Clear agent forwarding if we don't have an agent. */
|
|
if ((r = ssh_get_authentication_socket(NULL)) != 0) {
|
|
options.forward_agent = 0;
|
|
if (r != SSH_ERR_AGENT_NOT_PRESENT)
|
|
debug_r(r, "ssh_get_authentication_socket");
|
|
}
|
|
}
|
|
}
|
|
|
|
static void
|
|
ssh_session2_setup(struct ssh *ssh, int id, int success, void *arg)
|
|
{
|
|
extern char **environ;
|
|
const char *display, *term;
|
|
int r, interactive = tty_flag;
|
|
char *proto = NULL, *data = NULL;
|
|
|
|
if (!success)
|
|
return; /* No need for error message, channels code sens one */
|
|
|
|
display = getenv("DISPLAY");
|
|
if (display == NULL && options.forward_x11)
|
|
debug("X11 forwarding requested but DISPLAY not set");
|
|
if (options.forward_x11 && client_x11_get_proto(ssh, display,
|
|
options.xauth_location, options.forward_x11_trusted,
|
|
options.forward_x11_timeout, &proto, &data) == 0) {
|
|
/* Request forwarding with authentication spoofing. */
|
|
debug("Requesting X11 forwarding with authentication "
|
|
"spoofing.");
|
|
x11_request_forwarding_with_spoofing(ssh, id, display, proto,
|
|
data, 1);
|
|
client_expect_confirm(ssh, id, "X11 forwarding", CONFIRM_WARN);
|
|
/* XXX exit_on_forward_failure */
|
|
interactive = 1;
|
|
}
|
|
|
|
check_agent_present();
|
|
if (options.forward_agent) {
|
|
debug("Requesting authentication agent forwarding.");
|
|
channel_request_start(ssh, id, "auth-agent-req@openssh.com", 0);
|
|
if ((r = sshpkt_send(ssh)) != 0)
|
|
fatal_fr(r, "send packet");
|
|
}
|
|
|
|
/* Tell the packet module whether this is an interactive session. */
|
|
ssh_packet_set_interactive(ssh, interactive,
|
|
options.ip_qos_interactive, options.ip_qos_bulk);
|
|
|
|
if ((term = lookup_env_in_list("TERM", options.setenv,
|
|
options.num_setenv)) == NULL || *term == '\0')
|
|
term = getenv("TERM");
|
|
client_session2_setup(ssh, id, tty_flag,
|
|
options.session_type == SESSION_TYPE_SUBSYSTEM, term,
|
|
NULL, fileno(stdin), command, environ);
|
|
}
|
|
|
|
/* open new channel for a session */
|
|
static int
|
|
ssh_session2_open(struct ssh *ssh)
|
|
{
|
|
Channel *c;
|
|
int window, packetmax, in, out, err;
|
|
|
|
if (options.stdin_null) {
|
|
in = open(_PATH_DEVNULL, O_RDONLY);
|
|
} else {
|
|
in = dup(STDIN_FILENO);
|
|
}
|
|
out = dup(STDOUT_FILENO);
|
|
err = dup(STDERR_FILENO);
|
|
|
|
if (in == -1 || out == -1 || err == -1)
|
|
fatal("dup() in/out/err failed");
|
|
|
|
window = CHAN_SES_WINDOW_DEFAULT;
|
|
packetmax = CHAN_SES_PACKET_DEFAULT;
|
|
if (tty_flag) {
|
|
window >>= 1;
|
|
packetmax >>= 1;
|
|
}
|
|
c = channel_new(ssh,
|
|
"session", SSH_CHANNEL_OPENING, in, out, err,
|
|
window, packetmax, CHAN_EXTENDED_WRITE,
|
|
"client-session", CHANNEL_NONBLOCK_STDIO);
|
|
|
|
debug3_f("channel_new: %d", c->self);
|
|
|
|
channel_send_open(ssh, c->self);
|
|
if (options.session_type != SESSION_TYPE_NONE)
|
|
channel_register_open_confirm(ssh, c->self,
|
|
ssh_session2_setup, NULL);
|
|
|
|
return c->self;
|
|
}
|
|
|
|
static int
|
|
ssh_session2(struct ssh *ssh, const struct ssh_conn_info *cinfo)
|
|
{
|
|
int r, id = -1;
|
|
char *cp, *tun_fwd_ifname = NULL;
|
|
|
|
/* XXX should be pre-session */
|
|
if (!options.control_persist)
|
|
ssh_init_stdio_forwarding(ssh);
|
|
|
|
ssh_init_forwarding(ssh, &tun_fwd_ifname);
|
|
|
|
if (options.local_command != NULL) {
|
|
debug3("expanding LocalCommand: %s", options.local_command);
|
|
cp = options.local_command;
|
|
options.local_command = percent_expand(cp,
|
|
DEFAULT_CLIENT_PERCENT_EXPAND_ARGS(cinfo),
|
|
"T", tun_fwd_ifname == NULL ? "NONE" : tun_fwd_ifname,
|
|
(char *)NULL);
|
|
debug3("expanded LocalCommand: %s", options.local_command);
|
|
free(cp);
|
|
}
|
|
|
|
/* Start listening for multiplex clients */
|
|
if (!ssh_packet_get_mux(ssh))
|
|
muxserver_listen(ssh);
|
|
|
|
/*
|
|
* If we are in control persist mode and have a working mux listen
|
|
* socket, then prepare to background ourselves and have a foreground
|
|
* client attach as a control client.
|
|
* NB. we must save copies of the flags that we override for
|
|
* the backgrounding, since we defer attachment of the client 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 = options.stdin_null;
|
|
osession_type = options.session_type;
|
|
orequest_tty = options.request_tty;
|
|
otty_flag = tty_flag;
|
|
options.stdin_null = 1;
|
|
options.session_type = SESSION_TYPE_NONE;
|
|
tty_flag = 0;
|
|
if (!options.fork_after_authentication &&
|
|
(osession_type != SESSION_TYPE_NONE ||
|
|
options.stdio_forward_host != NULL))
|
|
need_controlpersist_detach = 1;
|
|
options.fork_after_authentication = 1;
|
|
}
|
|
/*
|
|
* ControlPersist mux listen socket setup failed, attempt the
|
|
* stdio forward setup that we skipped earlier.
|
|
*/
|
|
if (options.control_persist && muxserver_sock == -1)
|
|
ssh_init_stdio_forwarding(ssh);
|
|
|
|
if (options.session_type != SESSION_TYPE_NONE)
|
|
id = ssh_session2_open(ssh);
|
|
else {
|
|
ssh_packet_set_interactive(ssh,
|
|
options.control_master == SSHCTL_MASTER_NO,
|
|
options.ip_qos_interactive, options.ip_qos_bulk);
|
|
}
|
|
|
|
/* If we don't expect to open a new session, then disallow it */
|
|
if (options.control_master == SSHCTL_MASTER_NO &&
|
|
(ssh->compat & SSH_NEW_OPENSSH)) {
|
|
debug("Requesting no-more-sessions@openssh.com");
|
|
if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
|
|
(r = sshpkt_put_cstring(ssh,
|
|
"no-more-sessions@openssh.com")) != 0 ||
|
|
(r = sshpkt_put_u8(ssh, 0)) != 0 ||
|
|
(r = sshpkt_send(ssh)) != 0)
|
|
fatal_fr(r, "send packet");
|
|
}
|
|
|
|
/* Execute a local command */
|
|
if (options.local_command != NULL &&
|
|
options.permit_local_command)
|
|
ssh_local_cmd(options.local_command);
|
|
|
|
/*
|
|
* stdout is now owned by the session channel; clobber it here
|
|
* so future channel closes are propagated to the local fd.
|
|
* NB. this can only happen after LocalCommand has completed,
|
|
* as it may want to write to stdout.
|
|
*/
|
|
if (!need_controlpersist_detach && stdfd_devnull(0, 1, 0) == -1)
|
|
error_f("stdfd_devnull failed");
|
|
|
|
/*
|
|
* If requested and we are not interested in replies to remote
|
|
* forwarding requests, then let ssh continue in the background.
|
|
*/
|
|
if (options.fork_after_authentication) {
|
|
if (options.exit_on_forward_failure &&
|
|
options.num_remote_forwards > 0) {
|
|
debug("deferring postauth fork until remote forward "
|
|
"confirmation received");
|
|
} else
|
|
fork_postauth();
|
|
}
|
|
|
|
return client_loop(ssh, tty_flag, tty_flag ?
|
|
options.escape_char : SSH_ESCAPECHAR_NONE, id);
|
|
}
|
|
|
|
/* Loads all IdentityFile and CertificateFile keys */
|
|
static void
|
|
load_public_identity_files(const struct ssh_conn_info *cinfo)
|
|
{
|
|
char *filename, *cp;
|
|
struct sshkey *public;
|
|
int i;
|
|
u_int n_ids, n_certs;
|
|
char *identity_files[SSH_MAX_IDENTITY_FILES];
|
|
struct sshkey *identity_keys[SSH_MAX_IDENTITY_FILES];
|
|
int identity_file_userprovided[SSH_MAX_IDENTITY_FILES];
|
|
char *certificate_files[SSH_MAX_CERTIFICATE_FILES];
|
|
struct sshkey *certificates[SSH_MAX_CERTIFICATE_FILES];
|
|
int certificate_file_userprovided[SSH_MAX_CERTIFICATE_FILES];
|
|
#ifdef ENABLE_PKCS11
|
|
struct sshkey **keys = NULL;
|
|
char **comments = NULL;
|
|
int nkeys;
|
|
#endif /* PKCS11 */
|
|
|
|
n_ids = n_certs = 0;
|
|
memset(identity_files, 0, sizeof(identity_files));
|
|
memset(identity_keys, 0, sizeof(identity_keys));
|
|
memset(identity_file_userprovided, 0,
|
|
sizeof(identity_file_userprovided));
|
|
memset(certificate_files, 0, sizeof(certificate_files));
|
|
memset(certificates, 0, sizeof(certificates));
|
|
memset(certificate_file_userprovided, 0,
|
|
sizeof(certificate_file_userprovided));
|
|
|
|
#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, &comments)) > 0) {
|
|
for (i = 0; i < nkeys; i++) {
|
|
if (n_ids >= SSH_MAX_IDENTITY_FILES) {
|
|
sshkey_free(keys[i]);
|
|
free(comments[i]);
|
|
continue;
|
|
}
|
|
identity_keys[n_ids] = keys[i];
|
|
identity_files[n_ids] = comments[i]; /* transferred */
|
|
n_ids++;
|
|
}
|
|
free(keys);
|
|
free(comments);
|
|
}
|
|
#endif /* ENABLE_PKCS11 */
|
|
for (i = 0; i < options.num_identity_files; i++) {
|
|
if (n_ids >= SSH_MAX_IDENTITY_FILES ||
|
|
strcasecmp(options.identity_files[i], "none") == 0) {
|
|
free(options.identity_files[i]);
|
|
options.identity_files[i] = NULL;
|
|
continue;
|
|
}
|
|
cp = tilde_expand_filename(options.identity_files[i], getuid());
|
|
filename = default_client_percent_dollar_expand(cp, cinfo);
|
|
free(cp);
|
|
check_load(sshkey_load_public(filename, &public, NULL),
|
|
filename, "pubkey");
|
|
debug("identity file %s type %d", filename,
|
|
public ? public->type : -1);
|
|
free(options.identity_files[i]);
|
|
identity_files[n_ids] = filename;
|
|
identity_keys[n_ids] = public;
|
|
identity_file_userprovided[n_ids] =
|
|
options.identity_file_userprovided[i];
|
|
if (++n_ids >= SSH_MAX_IDENTITY_FILES)
|
|
continue;
|
|
|
|
/*
|
|
* If no certificates have been explicitly listed then try
|
|
* to add the default certificate variant too.
|
|
*/
|
|
if (options.num_certificate_files != 0)
|
|
continue;
|
|
xasprintf(&cp, "%s-cert", filename);
|
|
check_load(sshkey_load_public(cp, &public, NULL),
|
|
filename, "pubkey");
|
|
debug("identity file %s type %d", cp,
|
|
public ? public->type : -1);
|
|
if (public == NULL) {
|
|
free(cp);
|
|
continue;
|
|
}
|
|
if (!sshkey_is_cert(public)) {
|
|
debug_f("key %s type %s is not a certificate",
|
|
cp, sshkey_type(public));
|
|
sshkey_free(public);
|
|
free(cp);
|
|
continue;
|
|
}
|
|
/* NB. leave filename pointing to private key */
|
|
identity_files[n_ids] = xstrdup(filename);
|
|
identity_keys[n_ids] = public;
|
|
identity_file_userprovided[n_ids] =
|
|
options.identity_file_userprovided[i];
|
|
n_ids++;
|
|
}
|
|
|
|
if (options.num_certificate_files > SSH_MAX_CERTIFICATE_FILES)
|
|
fatal_f("too many certificates");
|
|
for (i = 0; i < options.num_certificate_files; i++) {
|
|
cp = tilde_expand_filename(options.certificate_files[i],
|
|
getuid());
|
|
filename = default_client_percent_dollar_expand(cp, cinfo);
|
|
free(cp);
|
|
|
|
check_load(sshkey_load_public(filename, &public, NULL),
|
|
filename, "certificate");
|
|
debug("certificate file %s type %d", filename,
|
|
public ? public->type : -1);
|
|
free(options.certificate_files[i]);
|
|
options.certificate_files[i] = NULL;
|
|
if (public == NULL) {
|
|
free(filename);
|
|
continue;
|
|
}
|
|
if (!sshkey_is_cert(public)) {
|
|
debug_f("key %s type %s is not a certificate",
|
|
filename, sshkey_type(public));
|
|
sshkey_free(public);
|
|
free(filename);
|
|
continue;
|
|
}
|
|
certificate_files[n_certs] = filename;
|
|
certificates[n_certs] = public;
|
|
certificate_file_userprovided[n_certs] =
|
|
options.certificate_file_userprovided[i];
|
|
++n_certs;
|
|
}
|
|
|
|
options.num_identity_files = n_ids;
|
|
memcpy(options.identity_files, identity_files, sizeof(identity_files));
|
|
memcpy(options.identity_keys, identity_keys, sizeof(identity_keys));
|
|
memcpy(options.identity_file_userprovided,
|
|
identity_file_userprovided, sizeof(identity_file_userprovided));
|
|
|
|
options.num_certificate_files = n_certs;
|
|
memcpy(options.certificate_files,
|
|
certificate_files, sizeof(certificate_files));
|
|
memcpy(options.certificates, certificates, sizeof(certificates));
|
|
memcpy(options.certificate_file_userprovided,
|
|
certificate_file_userprovided,
|
|
sizeof(certificate_file_userprovided));
|
|
}
|
|
|
|
static void
|
|
main_sigchld_handler(int sig)
|
|
{
|
|
int save_errno = errno;
|
|
pid_t pid;
|
|
int status;
|
|
|
|
while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
|
|
(pid == -1 && errno == EINTR))
|
|
;
|
|
errno = save_errno;
|
|
}
|