Some notable changes, from upstream's release notes: - sshd(8): Remove support for obsolete "host/port" syntax. - ssh(1): When prompting whether to record a new host key, accept the key fingerprint as a synonym for "yes". - ssh-keygen(1): when acting as a CA and signing certificates with an RSA key, default to using the rsa-sha2-512 signature algorithm. - ssh(1), sshd(8), ssh-keygen(1): this release removes the "ssh-rsa" (RSA/SHA1) algorithm from those accepted for certificate signatures. - ssh-sk-helper(8): this is a new binary. It is used by the FIDO/U2F support to provide address-space isolation for token middleware libraries (including the internal one). - ssh(1): this release enables UpdateHostkeys by default subject to some conservative preconditions. - scp(1): this release changes the behaviour of remote to remote copies (e.g. "scp host-a:/path host-b:") to transfer through the local host by default. - scp(1): experimental support for transfers using the SFTP protocol as a replacement for the venerable SCP/RCP protocol that it has traditionally used. Additional integration work is needed to support FIDO/U2F in the base system. Deprecation Notice ------------------ OpenSSH will disable the ssh-rsa signature scheme by default in the next release. Reviewed by: imp MFC after: 1 month Relnotes: Yes Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D29985
2529 lines
68 KiB
C
2529 lines
68 KiB
C
/* $OpenBSD: sshd.c,v 1.578 2021/07/19 02:21:50 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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* This program is the ssh daemon. It listens for connections from clients,
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* and performs authentication, executes use commands or shell, and forwards
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* information to/from the application to the user client over an encrypted
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* connection. This can also handle forwarding of X11, TCP/IP, and
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* authentication agent 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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* SSH2 implementation:
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* Privilege Separation:
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*
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* Copyright (c) 2000, 2001, 2002 Markus Friedl. All rights reserved.
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* Copyright (c) 2002 Niels Provos. All rights reserved.
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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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__RCSID("$FreeBSD$");
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#include <sys/types.h>
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#include <sys/ioctl.h>
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#include <sys/mman.h>
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#include <sys/socket.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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#ifdef HAVE_SYS_TIME_H
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# include <sys/time.h>
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#endif
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#include "openbsd-compat/sys-tree.h"
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#include "openbsd-compat/sys-queue.h"
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#include <sys/wait.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 <grp.h>
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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 <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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#include <limits.h>
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#ifdef WITH_OPENSSL
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#include <openssl/dh.h>
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#include <openssl/bn.h>
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#include <openssl/rand.h>
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#include "openbsd-compat/openssl-compat.h"
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#endif
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|
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#ifdef HAVE_SECUREWARE
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#include <sys/security.h>
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#include <prot.h>
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#endif
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#ifdef __FreeBSD__
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#include <resolv.h>
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#if defined(GSSAPI) && defined(HAVE_GSSAPI_GSSAPI_H)
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#include <gssapi/gssapi.h>
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#elif defined(GSSAPI) && defined(HAVE_GSSAPI_H)
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#include <gssapi.h>
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#endif
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#endif
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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 "sshpty.h"
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#include "packet.h"
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#include "log.h"
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#include "sshbuf.h"
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#include "misc.h"
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#include "match.h"
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#include "servconf.h"
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#include "uidswap.h"
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#include "compat.h"
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#include "cipher.h"
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#include "digest.h"
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#include "sshkey.h"
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#include "kex.h"
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#include "myproposal.h"
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#include "authfile.h"
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#include "pathnames.h"
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#include "atomicio.h"
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#include "canohost.h"
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#include "hostfile.h"
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#include "auth.h"
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#include "authfd.h"
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#include "msg.h"
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#include "dispatch.h"
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#include "channels.h"
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#include "session.h"
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#include "monitor.h"
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#ifdef GSSAPI
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#include "ssh-gss.h"
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#endif
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#include "monitor_wrap.h"
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#include "ssh-sandbox.h"
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#include "auth-options.h"
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#include "version.h"
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#include "ssherr.h"
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#include "sk-api.h"
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#include "srclimit.h"
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#include "dh.h"
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#include "blacklist_client.h"
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#ifdef LIBWRAP
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#include <tcpd.h>
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#include <syslog.h>
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int allow_severity;
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int deny_severity;
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#endif /* LIBWRAP */
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/* Re-exec fds */
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#define REEXEC_DEVCRYPTO_RESERVED_FD (STDERR_FILENO + 1)
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#define REEXEC_STARTUP_PIPE_FD (STDERR_FILENO + 2)
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#define REEXEC_CONFIG_PASS_FD (STDERR_FILENO + 3)
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#define REEXEC_MIN_FREE_FD (STDERR_FILENO + 4)
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extern char *__progname;
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/* Server configuration options. */
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ServerOptions options;
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/* Name of the server configuration file. */
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char *config_file_name = _PATH_SERVER_CONFIG_FILE;
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/*
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* Debug mode flag. This can be set on the command line. If debug
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* mode is enabled, extra debugging output will be sent to the system
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* log, the daemon will not go to background, and will exit after processing
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* the first connection.
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*/
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int debug_flag = 0;
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/*
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* Indicating that the daemon should only test the configuration and keys.
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* If test_flag > 1 ("-T" flag), then sshd will also dump the effective
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* configuration, optionally using connection information provided by the
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* "-C" flag.
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*/
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static int test_flag = 0;
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/* Flag indicating that the daemon is being started from inetd. */
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static int inetd_flag = 0;
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/* Flag indicating that sshd should not detach and become a daemon. */
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static int no_daemon_flag = 0;
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/* debug goes to stderr unless inetd_flag is set */
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static int log_stderr = 0;
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/* Saved arguments to main(). */
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static char **saved_argv;
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static int saved_argc;
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/* re-exec */
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static int rexeced_flag = 0;
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static int rexec_flag = 1;
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static int rexec_argc = 0;
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static char **rexec_argv;
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/*
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* The sockets that the server is listening; this is used in the SIGHUP
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* signal handler.
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*/
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#define MAX_LISTEN_SOCKS 16
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static int listen_socks[MAX_LISTEN_SOCKS];
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static int num_listen_socks = 0;
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/* Daemon's agent connection */
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int auth_sock = -1;
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static int have_agent = 0;
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/*
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* Any really sensitive data in the application is contained in this
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* structure. The idea is that this structure could be locked into memory so
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* that the pages do not get written into swap. However, there are some
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* problems. The private key contains BIGNUMs, and we do not (in principle)
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* have access to the internals of them, and locking just the structure is
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* not very useful. Currently, memory locking is not implemented.
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*/
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struct {
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struct sshkey **host_keys; /* all private host keys */
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struct sshkey **host_pubkeys; /* all public host keys */
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struct sshkey **host_certificates; /* all public host certificates */
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int have_ssh2_key;
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} sensitive_data;
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/* This is set to true when a signal is received. */
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static volatile sig_atomic_t received_sighup = 0;
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static volatile sig_atomic_t received_sigterm = 0;
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/* record remote hostname or ip */
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u_int utmp_len = HOST_NAME_MAX+1;
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/*
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* startup_pipes/flags are used for tracking children of the listening sshd
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* process early in their lifespans. This tracking is needed for three things:
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*
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* 1) Implementing the MaxStartups limit of concurrent unauthenticated
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* connections.
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* 2) Avoiding a race condition for SIGHUP processing, where child processes
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* may have listen_socks open that could collide with main listener process
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* after it restarts.
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* 3) Ensuring that rexec'd sshd processes have received their initial state
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* from the parent listen process before handling SIGHUP.
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*
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* Child processes signal that they have completed closure of the listen_socks
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* and (if applicable) received their rexec state by sending a char over their
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* sock. Child processes signal that authentication has completed by closing
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* the sock (or by exiting).
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*/
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static int *startup_pipes = NULL;
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static int *startup_flags = NULL; /* Indicates child closed listener */
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static int startup_pipe = -1; /* in child */
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/* variables used for privilege separation */
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int use_privsep = -1;
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struct monitor *pmonitor = NULL;
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int privsep_is_preauth = 1;
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static int privsep_chroot = 1;
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/* global connection state and authentication contexts */
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Authctxt *the_authctxt = NULL;
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struct ssh *the_active_state;
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/* global key/cert auth options. XXX move to permanent ssh->authctxt? */
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struct sshauthopt *auth_opts = NULL;
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/* sshd_config buffer */
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struct sshbuf *cfg;
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/* Included files from the configuration file */
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struct include_list includes = TAILQ_HEAD_INITIALIZER(includes);
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/* message to be displayed after login */
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struct sshbuf *loginmsg;
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/* Unprivileged user */
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struct passwd *privsep_pw = NULL;
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/* Prototypes for various functions defined later in this file. */
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void destroy_sensitive_data(void);
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void demote_sensitive_data(void);
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static void do_ssh2_kex(struct ssh *);
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static char *listener_proctitle;
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/*
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* Close all listening sockets
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*/
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static void
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close_listen_socks(void)
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{
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int i;
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for (i = 0; i < num_listen_socks; i++)
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close(listen_socks[i]);
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num_listen_socks = -1;
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}
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static void
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close_startup_pipes(void)
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{
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int i;
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if (startup_pipes)
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for (i = 0; i < options.max_startups; i++)
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if (startup_pipes[i] != -1)
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close(startup_pipes[i]);
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}
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/*
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* Signal handler for SIGHUP. Sshd execs itself when it receives SIGHUP;
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* the effect is to reread the configuration file (and to regenerate
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* the server key).
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*/
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/*ARGSUSED*/
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static void
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sighup_handler(int sig)
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{
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received_sighup = 1;
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}
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/*
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* Called from the main program after receiving SIGHUP.
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* Restarts the server.
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*/
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static void
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sighup_restart(void)
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{
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logit("Received SIGHUP; restarting.");
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if (options.pid_file != NULL)
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unlink(options.pid_file);
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platform_pre_restart();
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close_listen_socks();
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close_startup_pipes();
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ssh_signal(SIGHUP, SIG_IGN); /* will be restored after exec */
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execv(saved_argv[0], saved_argv);
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logit("RESTART FAILED: av[0]='%.100s', error: %.100s.", saved_argv[0],
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strerror(errno));
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exit(1);
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}
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/*
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* Generic signal handler for terminating signals in the master daemon.
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*/
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/*ARGSUSED*/
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static void
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sigterm_handler(int sig)
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{
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received_sigterm = sig;
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}
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/*
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* SIGCHLD handler. This is called whenever a child dies. This will then
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* reap any zombies left by exited children.
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*/
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/*ARGSUSED*/
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static void
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main_sigchld_handler(int sig)
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{
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int save_errno = errno;
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pid_t pid;
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int status;
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while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
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(pid == -1 && errno == EINTR))
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;
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errno = save_errno;
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}
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/*
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* Signal handler for the alarm after the login grace period has expired.
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*/
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/*ARGSUSED*/
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static void
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grace_alarm_handler(int sig)
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{
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if (use_privsep && pmonitor != NULL && pmonitor->m_pid > 0)
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kill(pmonitor->m_pid, SIGALRM);
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/*
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* Try to kill any processes that we have spawned, E.g. authorized
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* keys command helpers.
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*/
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if (getpgid(0) == getpid()) {
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ssh_signal(SIGTERM, SIG_IGN);
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kill(0, SIGTERM);
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}
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BLACKLIST_NOTIFY(BLACKLIST_AUTH_FAIL, "ssh");
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/* Log error and exit. */
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if (use_privsep && pmonitor != NULL && pmonitor->m_pid <= 0)
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cleanup_exit(255); /* don't log in privsep child */
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else {
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sigdie("Timeout before authentication for %s port %d",
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ssh_remote_ipaddr(the_active_state),
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ssh_remote_port(the_active_state));
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}
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}
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|
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/* Destroy the host and server keys. They will no longer be needed. */
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void
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destroy_sensitive_data(void)
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{
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u_int i;
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for (i = 0; i < options.num_host_key_files; i++) {
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if (sensitive_data.host_keys[i]) {
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sshkey_free(sensitive_data.host_keys[i]);
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sensitive_data.host_keys[i] = NULL;
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}
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if (sensitive_data.host_certificates[i]) {
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sshkey_free(sensitive_data.host_certificates[i]);
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sensitive_data.host_certificates[i] = NULL;
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}
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}
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}
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|
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/* Demote private to public keys for network child */
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void
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demote_sensitive_data(void)
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{
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struct sshkey *tmp;
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u_int i;
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int r;
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for (i = 0; i < options.num_host_key_files; i++) {
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if (sensitive_data.host_keys[i]) {
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if ((r = sshkey_from_private(
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sensitive_data.host_keys[i], &tmp)) != 0)
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fatal_r(r, "could not demote host %s key",
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sshkey_type(sensitive_data.host_keys[i]));
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sshkey_free(sensitive_data.host_keys[i]);
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sensitive_data.host_keys[i] = tmp;
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}
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/* Certs do not need demotion */
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}
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}
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|
|
static void
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|
reseed_prngs(void)
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|
{
|
|
u_int32_t rnd[256];
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|
#ifdef WITH_OPENSSL
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RAND_poll();
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|
#endif
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arc4random_stir(); /* noop on recent arc4random() implementations */
|
|
arc4random_buf(rnd, sizeof(rnd)); /* let arc4random notice PID change */
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|
|
#ifdef WITH_OPENSSL
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RAND_seed(rnd, sizeof(rnd));
|
|
/* give libcrypto a chance to notice the PID change */
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|
if ((RAND_bytes((u_char *)rnd, 1)) != 1)
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|
fatal("%s: RAND_bytes failed", __func__);
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|
#endif
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|
explicit_bzero(rnd, sizeof(rnd));
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}
|
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|
|
static void
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|
privsep_preauth_child(void)
|
|
{
|
|
gid_t gidset[1];
|
|
|
|
/* Enable challenge-response authentication for privilege separation */
|
|
privsep_challenge_enable();
|
|
|
|
#ifdef GSSAPI
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|
/* Cache supported mechanism OIDs for later use */
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|
ssh_gssapi_prepare_supported_oids();
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#endif
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|
|
|
reseed_prngs();
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|
|
|
/* Demote the private keys to public keys. */
|
|
demote_sensitive_data();
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|
|
|
/* Demote the child */
|
|
if (privsep_chroot) {
|
|
/* Change our root directory */
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|
if (chroot(_PATH_PRIVSEP_CHROOT_DIR) == -1)
|
|
fatal("chroot(\"%s\"): %s", _PATH_PRIVSEP_CHROOT_DIR,
|
|
strerror(errno));
|
|
if (chdir("/") == -1)
|
|
fatal("chdir(\"/\"): %s", strerror(errno));
|
|
|
|
/* Drop our privileges */
|
|
debug3("privsep user:group %u:%u", (u_int)privsep_pw->pw_uid,
|
|
(u_int)privsep_pw->pw_gid);
|
|
gidset[0] = privsep_pw->pw_gid;
|
|
if (setgroups(1, gidset) == -1)
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|
fatal("setgroups: %.100s", strerror(errno));
|
|
permanently_set_uid(privsep_pw);
|
|
}
|
|
}
|
|
|
|
static int
|
|
privsep_preauth(struct ssh *ssh)
|
|
{
|
|
int status, r;
|
|
pid_t pid;
|
|
struct ssh_sandbox *box = NULL;
|
|
|
|
/* Set up unprivileged child process to deal with network data */
|
|
pmonitor = monitor_init();
|
|
/* Store a pointer to the kex for later rekeying */
|
|
pmonitor->m_pkex = &ssh->kex;
|
|
|
|
if (use_privsep == PRIVSEP_ON)
|
|
box = ssh_sandbox_init(pmonitor);
|
|
pid = fork();
|
|
if (pid == -1) {
|
|
fatal("fork of unprivileged child failed");
|
|
} else if (pid != 0) {
|
|
debug2("Network child is on pid %ld", (long)pid);
|
|
|
|
pmonitor->m_pid = pid;
|
|
if (have_agent) {
|
|
r = ssh_get_authentication_socket(&auth_sock);
|
|
if (r != 0) {
|
|
error_r(r, "Could not get agent socket");
|
|
have_agent = 0;
|
|
}
|
|
}
|
|
if (box != NULL)
|
|
ssh_sandbox_parent_preauth(box, pid);
|
|
monitor_child_preauth(ssh, pmonitor);
|
|
|
|
/* Wait for the child's exit status */
|
|
while (waitpid(pid, &status, 0) == -1) {
|
|
if (errno == EINTR)
|
|
continue;
|
|
pmonitor->m_pid = -1;
|
|
fatal_f("waitpid: %s", strerror(errno));
|
|
}
|
|
privsep_is_preauth = 0;
|
|
pmonitor->m_pid = -1;
|
|
if (WIFEXITED(status)) {
|
|
if (WEXITSTATUS(status) != 0)
|
|
fatal_f("preauth child exited with status %d",
|
|
WEXITSTATUS(status));
|
|
} else if (WIFSIGNALED(status))
|
|
fatal_f("preauth child terminated by signal %d",
|
|
WTERMSIG(status));
|
|
if (box != NULL)
|
|
ssh_sandbox_parent_finish(box);
|
|
return 1;
|
|
} else {
|
|
/* child */
|
|
close(pmonitor->m_sendfd);
|
|
close(pmonitor->m_log_recvfd);
|
|
|
|
/* Arrange for logging to be sent to the monitor */
|
|
set_log_handler(mm_log_handler, pmonitor);
|
|
|
|
privsep_preauth_child();
|
|
setproctitle("%s", "[net]");
|
|
if (box != NULL)
|
|
ssh_sandbox_child(box);
|
|
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
static void
|
|
privsep_postauth(struct ssh *ssh, Authctxt *authctxt)
|
|
{
|
|
#ifdef DISABLE_FD_PASSING
|
|
if (1) {
|
|
#else
|
|
if (authctxt->pw->pw_uid == 0) {
|
|
#endif
|
|
/* File descriptor passing is broken or root login */
|
|
use_privsep = 0;
|
|
goto skip;
|
|
}
|
|
|
|
/* New socket pair */
|
|
monitor_reinit(pmonitor);
|
|
|
|
pmonitor->m_pid = fork();
|
|
if (pmonitor->m_pid == -1)
|
|
fatal("fork of unprivileged child failed");
|
|
else if (pmonitor->m_pid != 0) {
|
|
verbose("User child is on pid %ld", (long)pmonitor->m_pid);
|
|
sshbuf_reset(loginmsg);
|
|
monitor_clear_keystate(ssh, pmonitor);
|
|
monitor_child_postauth(ssh, pmonitor);
|
|
|
|
/* NEVERREACHED */
|
|
exit(0);
|
|
}
|
|
|
|
/* child */
|
|
|
|
close(pmonitor->m_sendfd);
|
|
pmonitor->m_sendfd = -1;
|
|
|
|
/* Demote the private keys to public keys. */
|
|
demote_sensitive_data();
|
|
|
|
reseed_prngs();
|
|
|
|
/* Drop privileges */
|
|
do_setusercontext(authctxt->pw);
|
|
|
|
skip:
|
|
/* It is safe now to apply the key state */
|
|
monitor_apply_keystate(ssh, pmonitor);
|
|
|
|
/*
|
|
* Tell the packet layer that authentication was successful, since
|
|
* this information is not part of the key state.
|
|
*/
|
|
ssh_packet_set_authenticated(ssh);
|
|
}
|
|
|
|
static void
|
|
append_hostkey_type(struct sshbuf *b, const char *s)
|
|
{
|
|
int r;
|
|
|
|
if (match_pattern_list(s, options.hostkeyalgorithms, 0) != 1) {
|
|
debug3_f("%s key not permitted by HostkeyAlgorithms", s);
|
|
return;
|
|
}
|
|
if ((r = sshbuf_putf(b, "%s%s", sshbuf_len(b) > 0 ? "," : "", s)) != 0)
|
|
fatal_fr(r, "sshbuf_putf");
|
|
}
|
|
|
|
static char *
|
|
list_hostkey_types(void)
|
|
{
|
|
struct sshbuf *b;
|
|
struct sshkey *key;
|
|
char *ret;
|
|
u_int i;
|
|
|
|
if ((b = sshbuf_new()) == NULL)
|
|
fatal_f("sshbuf_new failed");
|
|
for (i = 0; i < options.num_host_key_files; i++) {
|
|
key = sensitive_data.host_keys[i];
|
|
if (key == NULL)
|
|
key = sensitive_data.host_pubkeys[i];
|
|
if (key == NULL)
|
|
continue;
|
|
switch (key->type) {
|
|
case KEY_RSA:
|
|
/* for RSA we also support SHA2 signatures */
|
|
append_hostkey_type(b, "rsa-sha2-512");
|
|
append_hostkey_type(b, "rsa-sha2-256");
|
|
/* FALLTHROUGH */
|
|
case KEY_DSA:
|
|
case KEY_ECDSA:
|
|
case KEY_ED25519:
|
|
case KEY_ECDSA_SK:
|
|
case KEY_ED25519_SK:
|
|
case KEY_XMSS:
|
|
append_hostkey_type(b, sshkey_ssh_name(key));
|
|
break;
|
|
}
|
|
/* If the private key has a cert peer, then list that too */
|
|
key = sensitive_data.host_certificates[i];
|
|
if (key == NULL)
|
|
continue;
|
|
switch (key->type) {
|
|
case KEY_RSA_CERT:
|
|
/* for RSA we also support SHA2 signatures */
|
|
append_hostkey_type(b,
|
|
"rsa-sha2-512-cert-v01@openssh.com");
|
|
append_hostkey_type(b,
|
|
"rsa-sha2-256-cert-v01@openssh.com");
|
|
/* FALLTHROUGH */
|
|
case KEY_DSA_CERT:
|
|
case KEY_ECDSA_CERT:
|
|
case KEY_ED25519_CERT:
|
|
case KEY_ECDSA_SK_CERT:
|
|
case KEY_ED25519_SK_CERT:
|
|
case KEY_XMSS_CERT:
|
|
append_hostkey_type(b, sshkey_ssh_name(key));
|
|
break;
|
|
}
|
|
}
|
|
if ((ret = sshbuf_dup_string(b)) == NULL)
|
|
fatal_f("sshbuf_dup_string failed");
|
|
sshbuf_free(b);
|
|
debug_f("%s", ret);
|
|
return ret;
|
|
}
|
|
|
|
static struct sshkey *
|
|
get_hostkey_by_type(int type, int nid, int need_private, struct ssh *ssh)
|
|
{
|
|
u_int i;
|
|
struct sshkey *key;
|
|
|
|
for (i = 0; i < options.num_host_key_files; i++) {
|
|
switch (type) {
|
|
case KEY_RSA_CERT:
|
|
case KEY_DSA_CERT:
|
|
case KEY_ECDSA_CERT:
|
|
case KEY_ED25519_CERT:
|
|
case KEY_ECDSA_SK_CERT:
|
|
case KEY_ED25519_SK_CERT:
|
|
case KEY_XMSS_CERT:
|
|
key = sensitive_data.host_certificates[i];
|
|
break;
|
|
default:
|
|
key = sensitive_data.host_keys[i];
|
|
if (key == NULL && !need_private)
|
|
key = sensitive_data.host_pubkeys[i];
|
|
break;
|
|
}
|
|
if (key == NULL || key->type != type)
|
|
continue;
|
|
switch (type) {
|
|
case KEY_ECDSA:
|
|
case KEY_ECDSA_SK:
|
|
case KEY_ECDSA_CERT:
|
|
case KEY_ECDSA_SK_CERT:
|
|
if (key->ecdsa_nid != nid)
|
|
continue;
|
|
/* FALLTHROUGH */
|
|
default:
|
|
return need_private ?
|
|
sensitive_data.host_keys[i] : key;
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
struct sshkey *
|
|
get_hostkey_public_by_type(int type, int nid, struct ssh *ssh)
|
|
{
|
|
return get_hostkey_by_type(type, nid, 0, ssh);
|
|
}
|
|
|
|
struct sshkey *
|
|
get_hostkey_private_by_type(int type, int nid, struct ssh *ssh)
|
|
{
|
|
return get_hostkey_by_type(type, nid, 1, ssh);
|
|
}
|
|
|
|
struct sshkey *
|
|
get_hostkey_by_index(int ind)
|
|
{
|
|
if (ind < 0 || (u_int)ind >= options.num_host_key_files)
|
|
return (NULL);
|
|
return (sensitive_data.host_keys[ind]);
|
|
}
|
|
|
|
struct sshkey *
|
|
get_hostkey_public_by_index(int ind, struct ssh *ssh)
|
|
{
|
|
if (ind < 0 || (u_int)ind >= options.num_host_key_files)
|
|
return (NULL);
|
|
return (sensitive_data.host_pubkeys[ind]);
|
|
}
|
|
|
|
int
|
|
get_hostkey_index(struct sshkey *key, int compare, struct ssh *ssh)
|
|
{
|
|
u_int i;
|
|
|
|
for (i = 0; i < options.num_host_key_files; i++) {
|
|
if (sshkey_is_cert(key)) {
|
|
if (key == sensitive_data.host_certificates[i] ||
|
|
(compare && sensitive_data.host_certificates[i] &&
|
|
sshkey_equal(key,
|
|
sensitive_data.host_certificates[i])))
|
|
return (i);
|
|
} else {
|
|
if (key == sensitive_data.host_keys[i] ||
|
|
(compare && sensitive_data.host_keys[i] &&
|
|
sshkey_equal(key, sensitive_data.host_keys[i])))
|
|
return (i);
|
|
if (key == sensitive_data.host_pubkeys[i] ||
|
|
(compare && sensitive_data.host_pubkeys[i] &&
|
|
sshkey_equal(key, sensitive_data.host_pubkeys[i])))
|
|
return (i);
|
|
}
|
|
}
|
|
return (-1);
|
|
}
|
|
|
|
/* Inform the client of all hostkeys */
|
|
static void
|
|
notify_hostkeys(struct ssh *ssh)
|
|
{
|
|
struct sshbuf *buf;
|
|
struct sshkey *key;
|
|
u_int i, nkeys;
|
|
int r;
|
|
char *fp;
|
|
|
|
/* Some clients cannot cope with the hostkeys message, skip those. */
|
|
if (ssh->compat & SSH_BUG_HOSTKEYS)
|
|
return;
|
|
|
|
if ((buf = sshbuf_new()) == NULL)
|
|
fatal_f("sshbuf_new");
|
|
for (i = nkeys = 0; i < options.num_host_key_files; i++) {
|
|
key = get_hostkey_public_by_index(i, ssh);
|
|
if (key == NULL || key->type == KEY_UNSPEC ||
|
|
sshkey_is_cert(key))
|
|
continue;
|
|
fp = sshkey_fingerprint(key, options.fingerprint_hash,
|
|
SSH_FP_DEFAULT);
|
|
debug3_f("key %d: %s %s", i, sshkey_ssh_name(key), fp);
|
|
free(fp);
|
|
if (nkeys == 0) {
|
|
/*
|
|
* Start building the request when we find the
|
|
* first usable key.
|
|
*/
|
|
if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
|
|
(r = sshpkt_put_cstring(ssh, "hostkeys-00@openssh.com")) != 0 ||
|
|
(r = sshpkt_put_u8(ssh, 0)) != 0) /* want reply */
|
|
sshpkt_fatal(ssh, r, "%s: start request", __func__);
|
|
}
|
|
/* Append the key to the request */
|
|
sshbuf_reset(buf);
|
|
if ((r = sshkey_putb(key, buf)) != 0)
|
|
fatal_fr(r, "couldn't put hostkey %d", i);
|
|
if ((r = sshpkt_put_stringb(ssh, buf)) != 0)
|
|
sshpkt_fatal(ssh, r, "%s: append key", __func__);
|
|
nkeys++;
|
|
}
|
|
debug3_f("sent %u hostkeys", nkeys);
|
|
if (nkeys == 0)
|
|
fatal_f("no hostkeys");
|
|
if ((r = sshpkt_send(ssh)) != 0)
|
|
sshpkt_fatal(ssh, r, "%s: send", __func__);
|
|
sshbuf_free(buf);
|
|
}
|
|
|
|
/*
|
|
* returns 1 if connection should be dropped, 0 otherwise.
|
|
* dropping starts at connection #max_startups_begin with a probability
|
|
* of (max_startups_rate/100). the probability increases linearly until
|
|
* all connections are dropped for startups > max_startups
|
|
*/
|
|
static int
|
|
should_drop_connection(int startups)
|
|
{
|
|
int p, r;
|
|
|
|
if (startups < options.max_startups_begin)
|
|
return 0;
|
|
if (startups >= options.max_startups)
|
|
return 1;
|
|
if (options.max_startups_rate == 100)
|
|
return 1;
|
|
|
|
p = 100 - options.max_startups_rate;
|
|
p *= startups - options.max_startups_begin;
|
|
p /= options.max_startups - options.max_startups_begin;
|
|
p += options.max_startups_rate;
|
|
r = arc4random_uniform(100);
|
|
|
|
debug_f("p %d, r %d", p, r);
|
|
return (r < p) ? 1 : 0;
|
|
}
|
|
|
|
/*
|
|
* Check whether connection should be accepted by MaxStartups.
|
|
* Returns 0 if the connection is accepted. If the connection is refused,
|
|
* returns 1 and attempts to send notification to client.
|
|
* Logs when the MaxStartups condition is entered or exited, and periodically
|
|
* while in that state.
|
|
*/
|
|
static int
|
|
drop_connection(int sock, int startups, int notify_pipe)
|
|
{
|
|
char *laddr, *raddr;
|
|
const char msg[] = "Exceeded MaxStartups\r\n";
|
|
static time_t last_drop, first_drop;
|
|
static u_int ndropped;
|
|
LogLevel drop_level = SYSLOG_LEVEL_VERBOSE;
|
|
time_t now;
|
|
|
|
now = monotime();
|
|
if (!should_drop_connection(startups) &&
|
|
srclimit_check_allow(sock, notify_pipe) == 1) {
|
|
if (last_drop != 0 &&
|
|
startups < options.max_startups_begin - 1) {
|
|
/* XXX maybe need better hysteresis here */
|
|
logit("exited MaxStartups throttling after %s, "
|
|
"%u connections dropped",
|
|
fmt_timeframe(now - first_drop), ndropped);
|
|
last_drop = 0;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
#define SSHD_MAXSTARTUPS_LOG_INTERVAL (5 * 60)
|
|
if (last_drop == 0) {
|
|
error("beginning MaxStartups throttling");
|
|
drop_level = SYSLOG_LEVEL_INFO;
|
|
first_drop = now;
|
|
ndropped = 0;
|
|
} else if (last_drop + SSHD_MAXSTARTUPS_LOG_INTERVAL < now) {
|
|
/* Periodic logs */
|
|
error("in MaxStartups throttling for %s, "
|
|
"%u connections dropped",
|
|
fmt_timeframe(now - first_drop), ndropped + 1);
|
|
drop_level = SYSLOG_LEVEL_INFO;
|
|
}
|
|
last_drop = now;
|
|
ndropped++;
|
|
|
|
laddr = get_local_ipaddr(sock);
|
|
raddr = get_peer_ipaddr(sock);
|
|
do_log2(drop_level, "drop connection #%d from [%s]:%d on [%s]:%d "
|
|
"past MaxStartups", startups, raddr, get_peer_port(sock),
|
|
laddr, get_local_port(sock));
|
|
free(laddr);
|
|
free(raddr);
|
|
/* best-effort notification to client */
|
|
(void)write(sock, msg, sizeof(msg) - 1);
|
|
return 1;
|
|
}
|
|
|
|
static void
|
|
usage(void)
|
|
{
|
|
if (options.version_addendum && *options.version_addendum != '\0')
|
|
fprintf(stderr, "%s %s, %s\n",
|
|
SSH_RELEASE,
|
|
options.version_addendum, OPENSSL_VERSION_STRING);
|
|
else
|
|
fprintf(stderr, "%s, %s\n",
|
|
SSH_RELEASE, OPENSSL_VERSION_STRING);
|
|
fprintf(stderr,
|
|
"usage: sshd [-46DdeiqTt] [-C connection_spec] [-c host_cert_file]\n"
|
|
" [-E log_file] [-f config_file] [-g login_grace_time]\n"
|
|
" [-h host_key_file] [-o option] [-p port] [-u len]\n"
|
|
);
|
|
exit(1);
|
|
}
|
|
|
|
static void
|
|
send_rexec_state(int fd, struct sshbuf *conf)
|
|
{
|
|
struct sshbuf *m = NULL, *inc = NULL;
|
|
struct include_item *item = NULL;
|
|
int r;
|
|
|
|
debug3_f("entering fd = %d config len %zu", fd,
|
|
sshbuf_len(conf));
|
|
|
|
if ((m = sshbuf_new()) == NULL || (inc = sshbuf_new()) == NULL)
|
|
fatal_f("sshbuf_new failed");
|
|
|
|
/* pack includes into a string */
|
|
TAILQ_FOREACH(item, &includes, entry) {
|
|
if ((r = sshbuf_put_cstring(inc, item->selector)) != 0 ||
|
|
(r = sshbuf_put_cstring(inc, item->filename)) != 0 ||
|
|
(r = sshbuf_put_stringb(inc, item->contents)) != 0)
|
|
fatal_fr(r, "compose includes");
|
|
}
|
|
|
|
/*
|
|
* Protocol from reexec master to child:
|
|
* string configuration
|
|
* string included_files[] {
|
|
* string selector
|
|
* string filename
|
|
* string contents
|
|
* }
|
|
* string rng_seed (if required)
|
|
*/
|
|
if ((r = sshbuf_put_stringb(m, conf)) != 0 ||
|
|
(r = sshbuf_put_stringb(m, inc)) != 0)
|
|
fatal_fr(r, "compose config");
|
|
#if defined(WITH_OPENSSL) && !defined(OPENSSL_PRNG_ONLY)
|
|
rexec_send_rng_seed(m);
|
|
#endif
|
|
if (ssh_msg_send(fd, 0, m) == -1)
|
|
error_f("ssh_msg_send failed");
|
|
|
|
sshbuf_free(m);
|
|
sshbuf_free(inc);
|
|
|
|
debug3_f("done");
|
|
}
|
|
|
|
static void
|
|
recv_rexec_state(int fd, struct sshbuf *conf)
|
|
{
|
|
struct sshbuf *m, *inc;
|
|
u_char *cp, ver;
|
|
size_t len;
|
|
int r;
|
|
struct include_item *item;
|
|
|
|
debug3_f("entering fd = %d", fd);
|
|
|
|
if ((m = sshbuf_new()) == NULL || (inc = sshbuf_new()) == NULL)
|
|
fatal_f("sshbuf_new failed");
|
|
if (ssh_msg_recv(fd, m) == -1)
|
|
fatal_f("ssh_msg_recv failed");
|
|
if ((r = sshbuf_get_u8(m, &ver)) != 0)
|
|
fatal_fr(r, "parse version");
|
|
if (ver != 0)
|
|
fatal_f("rexec version mismatch");
|
|
if ((r = sshbuf_get_string(m, &cp, &len)) != 0 ||
|
|
(r = sshbuf_get_stringb(m, inc)) != 0)
|
|
fatal_fr(r, "parse config");
|
|
|
|
#if defined(WITH_OPENSSL) && !defined(OPENSSL_PRNG_ONLY)
|
|
rexec_recv_rng_seed(m);
|
|
#endif
|
|
|
|
if (conf != NULL && (r = sshbuf_put(conf, cp, len)))
|
|
fatal_fr(r, "sshbuf_put");
|
|
|
|
while (sshbuf_len(inc) != 0) {
|
|
item = xcalloc(1, sizeof(*item));
|
|
if ((item->contents = sshbuf_new()) == NULL)
|
|
fatal_f("sshbuf_new failed");
|
|
if ((r = sshbuf_get_cstring(inc, &item->selector, NULL)) != 0 ||
|
|
(r = sshbuf_get_cstring(inc, &item->filename, NULL)) != 0 ||
|
|
(r = sshbuf_get_stringb(inc, item->contents)) != 0)
|
|
fatal_fr(r, "parse includes");
|
|
TAILQ_INSERT_TAIL(&includes, item, entry);
|
|
}
|
|
|
|
free(cp);
|
|
sshbuf_free(m);
|
|
|
|
debug3_f("done");
|
|
}
|
|
|
|
/* Accept a connection from inetd */
|
|
static void
|
|
server_accept_inetd(int *sock_in, int *sock_out)
|
|
{
|
|
if (rexeced_flag) {
|
|
close(REEXEC_CONFIG_PASS_FD);
|
|
*sock_in = *sock_out = dup(STDIN_FILENO);
|
|
} else {
|
|
*sock_in = dup(STDIN_FILENO);
|
|
*sock_out = dup(STDOUT_FILENO);
|
|
}
|
|
/*
|
|
* We intentionally do not close the descriptors 0, 1, and 2
|
|
* as our code for setting the descriptors won't work if
|
|
* ttyfd happens to be one of those.
|
|
*/
|
|
if (stdfd_devnull(1, 1, !log_stderr) == -1)
|
|
error_f("stdfd_devnull failed");
|
|
debug("inetd sockets after dupping: %d, %d", *sock_in, *sock_out);
|
|
}
|
|
|
|
/*
|
|
* Listen for TCP connections
|
|
*/
|
|
static void
|
|
listen_on_addrs(struct listenaddr *la)
|
|
{
|
|
int ret, listen_sock;
|
|
struct addrinfo *ai;
|
|
char ntop[NI_MAXHOST], strport[NI_MAXSERV];
|
|
|
|
for (ai = la->addrs; ai; ai = ai->ai_next) {
|
|
if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
|
|
continue;
|
|
if (num_listen_socks >= MAX_LISTEN_SOCKS)
|
|
fatal("Too many listen sockets. "
|
|
"Enlarge MAX_LISTEN_SOCKS");
|
|
if ((ret = getnameinfo(ai->ai_addr, ai->ai_addrlen,
|
|
ntop, sizeof(ntop), strport, sizeof(strport),
|
|
NI_NUMERICHOST|NI_NUMERICSERV)) != 0) {
|
|
error("getnameinfo failed: %.100s",
|
|
ssh_gai_strerror(ret));
|
|
continue;
|
|
}
|
|
/* Create socket for listening. */
|
|
listen_sock = socket(ai->ai_family, ai->ai_socktype,
|
|
ai->ai_protocol);
|
|
if (listen_sock == -1) {
|
|
/* kernel may not support ipv6 */
|
|
verbose("socket: %.100s", strerror(errno));
|
|
continue;
|
|
}
|
|
if (set_nonblock(listen_sock) == -1) {
|
|
close(listen_sock);
|
|
continue;
|
|
}
|
|
if (fcntl(listen_sock, F_SETFD, FD_CLOEXEC) == -1) {
|
|
verbose("socket: CLOEXEC: %s", strerror(errno));
|
|
close(listen_sock);
|
|
continue;
|
|
}
|
|
/* Socket options */
|
|
set_reuseaddr(listen_sock);
|
|
if (la->rdomain != NULL &&
|
|
set_rdomain(listen_sock, la->rdomain) == -1) {
|
|
close(listen_sock);
|
|
continue;
|
|
}
|
|
|
|
/* Only communicate in IPv6 over AF_INET6 sockets. */
|
|
if (ai->ai_family == AF_INET6)
|
|
sock_set_v6only(listen_sock);
|
|
|
|
debug("Bind to port %s on %s.", strport, ntop);
|
|
|
|
/* Bind the socket to the desired port. */
|
|
if (bind(listen_sock, ai->ai_addr, ai->ai_addrlen) == -1) {
|
|
error("Bind to port %s on %s failed: %.200s.",
|
|
strport, ntop, strerror(errno));
|
|
close(listen_sock);
|
|
continue;
|
|
}
|
|
listen_socks[num_listen_socks] = listen_sock;
|
|
num_listen_socks++;
|
|
|
|
/* Start listening on the port. */
|
|
if (listen(listen_sock, SSH_LISTEN_BACKLOG) == -1)
|
|
fatal("listen on [%s]:%s: %.100s",
|
|
ntop, strport, strerror(errno));
|
|
logit("Server listening on %s port %s%s%s.",
|
|
ntop, strport,
|
|
la->rdomain == NULL ? "" : " rdomain ",
|
|
la->rdomain == NULL ? "" : la->rdomain);
|
|
}
|
|
}
|
|
|
|
static void
|
|
server_listen(void)
|
|
{
|
|
u_int i;
|
|
|
|
/* Initialise per-source limit tracking. */
|
|
srclimit_init(options.max_startups, options.per_source_max_startups,
|
|
options.per_source_masklen_ipv4, options.per_source_masklen_ipv6);
|
|
|
|
for (i = 0; i < options.num_listen_addrs; i++) {
|
|
listen_on_addrs(&options.listen_addrs[i]);
|
|
freeaddrinfo(options.listen_addrs[i].addrs);
|
|
free(options.listen_addrs[i].rdomain);
|
|
memset(&options.listen_addrs[i], 0,
|
|
sizeof(options.listen_addrs[i]));
|
|
}
|
|
free(options.listen_addrs);
|
|
options.listen_addrs = NULL;
|
|
options.num_listen_addrs = 0;
|
|
|
|
if (!num_listen_socks)
|
|
fatal("Cannot bind any address.");
|
|
}
|
|
|
|
/*
|
|
* The main TCP accept loop. Note that, for the non-debug case, returns
|
|
* from this function are in a forked subprocess.
|
|
*/
|
|
static void
|
|
server_accept_loop(int *sock_in, int *sock_out, int *newsock, int *config_s)
|
|
{
|
|
fd_set *fdset;
|
|
int i, j, ret, maxfd;
|
|
int ostartups = -1, startups = 0, listening = 0, lameduck = 0;
|
|
int startup_p[2] = { -1 , -1 };
|
|
char c = 0;
|
|
struct sockaddr_storage from;
|
|
socklen_t fromlen;
|
|
pid_t pid;
|
|
u_char rnd[256];
|
|
sigset_t nsigset, osigset;
|
|
|
|
/* setup fd set for accept */
|
|
fdset = NULL;
|
|
maxfd = 0;
|
|
for (i = 0; i < num_listen_socks; i++)
|
|
if (listen_socks[i] > maxfd)
|
|
maxfd = listen_socks[i];
|
|
/* pipes connected to unauthenticated child sshd processes */
|
|
startup_pipes = xcalloc(options.max_startups, sizeof(int));
|
|
startup_flags = xcalloc(options.max_startups, sizeof(int));
|
|
for (i = 0; i < options.max_startups; i++)
|
|
startup_pipes[i] = -1;
|
|
|
|
/*
|
|
* Prepare signal mask that we use to block signals that might set
|
|
* received_sigterm or received_sighup, so that we are guaranteed
|
|
* to immediately wake up the pselect if a signal is received after
|
|
* the flag is checked.
|
|
*/
|
|
sigemptyset(&nsigset);
|
|
sigaddset(&nsigset, SIGHUP);
|
|
sigaddset(&nsigset, SIGCHLD);
|
|
sigaddset(&nsigset, SIGTERM);
|
|
sigaddset(&nsigset, SIGQUIT);
|
|
|
|
/*
|
|
* Stay listening for connections until the system crashes or
|
|
* the daemon is killed with a signal.
|
|
*/
|
|
for (;;) {
|
|
sigprocmask(SIG_BLOCK, &nsigset, &osigset);
|
|
if (received_sigterm) {
|
|
logit("Received signal %d; terminating.",
|
|
(int) received_sigterm);
|
|
close_listen_socks();
|
|
if (options.pid_file != NULL)
|
|
unlink(options.pid_file);
|
|
exit(received_sigterm == SIGTERM ? 0 : 255);
|
|
}
|
|
if (ostartups != startups) {
|
|
setproctitle("%s [listener] %d of %d-%d startups",
|
|
listener_proctitle, startups,
|
|
options.max_startups_begin, options.max_startups);
|
|
ostartups = startups;
|
|
}
|
|
if (received_sighup) {
|
|
if (!lameduck) {
|
|
debug("Received SIGHUP; waiting for children");
|
|
close_listen_socks();
|
|
lameduck = 1;
|
|
}
|
|
if (listening <= 0) {
|
|
sigprocmask(SIG_SETMASK, &osigset, NULL);
|
|
sighup_restart();
|
|
}
|
|
}
|
|
free(fdset);
|
|
fdset = xcalloc(howmany(maxfd + 1, NFDBITS),
|
|
sizeof(fd_mask));
|
|
|
|
for (i = 0; i < num_listen_socks; i++)
|
|
FD_SET(listen_socks[i], fdset);
|
|
for (i = 0; i < options.max_startups; i++)
|
|
if (startup_pipes[i] != -1)
|
|
FD_SET(startup_pipes[i], fdset);
|
|
|
|
/* Wait until a connection arrives or a child exits. */
|
|
ret = pselect(maxfd+1, fdset, NULL, NULL, NULL, &osigset);
|
|
if (ret == -1 && errno != EINTR)
|
|
error("pselect: %.100s", strerror(errno));
|
|
sigprocmask(SIG_SETMASK, &osigset, NULL);
|
|
if (ret == -1)
|
|
continue;
|
|
|
|
for (i = 0; i < options.max_startups; i++) {
|
|
if (startup_pipes[i] == -1 ||
|
|
!FD_ISSET(startup_pipes[i], fdset))
|
|
continue;
|
|
switch (read(startup_pipes[i], &c, sizeof(c))) {
|
|
case -1:
|
|
if (errno == EINTR || errno == EAGAIN)
|
|
continue;
|
|
if (errno != EPIPE) {
|
|
error_f("startup pipe %d (fd=%d): "
|
|
"read %s", i, startup_pipes[i],
|
|
strerror(errno));
|
|
}
|
|
/* FALLTHROUGH */
|
|
case 0:
|
|
/* child exited or completed auth */
|
|
close(startup_pipes[i]);
|
|
srclimit_done(startup_pipes[i]);
|
|
startup_pipes[i] = -1;
|
|
startups--;
|
|
if (startup_flags[i])
|
|
listening--;
|
|
break;
|
|
case 1:
|
|
/* child has finished preliminaries */
|
|
if (startup_flags[i]) {
|
|
listening--;
|
|
startup_flags[i] = 0;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
for (i = 0; i < num_listen_socks; i++) {
|
|
if (!FD_ISSET(listen_socks[i], fdset))
|
|
continue;
|
|
fromlen = sizeof(from);
|
|
*newsock = accept(listen_socks[i],
|
|
(struct sockaddr *)&from, &fromlen);
|
|
if (*newsock == -1) {
|
|
if (errno != EINTR && errno != EWOULDBLOCK &&
|
|
errno != ECONNABORTED && errno != EAGAIN)
|
|
error("accept: %.100s",
|
|
strerror(errno));
|
|
if (errno == EMFILE || errno == ENFILE)
|
|
usleep(100 * 1000);
|
|
continue;
|
|
}
|
|
if (unset_nonblock(*newsock) == -1 ||
|
|
pipe(startup_p) == -1)
|
|
continue;
|
|
if (drop_connection(*newsock, startups, startup_p[0])) {
|
|
close(*newsock);
|
|
close(startup_p[0]);
|
|
close(startup_p[1]);
|
|
continue;
|
|
}
|
|
|
|
if (rexec_flag && socketpair(AF_UNIX,
|
|
SOCK_STREAM, 0, config_s) == -1) {
|
|
error("reexec socketpair: %s",
|
|
strerror(errno));
|
|
close(*newsock);
|
|
close(startup_p[0]);
|
|
close(startup_p[1]);
|
|
continue;
|
|
}
|
|
|
|
for (j = 0; j < options.max_startups; j++)
|
|
if (startup_pipes[j] == -1) {
|
|
startup_pipes[j] = startup_p[0];
|
|
if (maxfd < startup_p[0])
|
|
maxfd = startup_p[0];
|
|
startups++;
|
|
startup_flags[j] = 1;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Got connection. Fork a child to handle it, unless
|
|
* we are in debugging mode.
|
|
*/
|
|
if (debug_flag) {
|
|
/*
|
|
* In debugging mode. Close the listening
|
|
* socket, and start processing the
|
|
* connection without forking.
|
|
*/
|
|
debug("Server will not fork when running in debugging mode.");
|
|
close_listen_socks();
|
|
*sock_in = *newsock;
|
|
*sock_out = *newsock;
|
|
close(startup_p[0]);
|
|
close(startup_p[1]);
|
|
startup_pipe = -1;
|
|
pid = getpid();
|
|
if (rexec_flag) {
|
|
send_rexec_state(config_s[0], cfg);
|
|
close(config_s[0]);
|
|
}
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Normal production daemon. Fork, and have
|
|
* the child process the connection. The
|
|
* parent continues listening.
|
|
*/
|
|
platform_pre_fork();
|
|
listening++;
|
|
if ((pid = fork()) == 0) {
|
|
/*
|
|
* Child. Close the listening and
|
|
* max_startup sockets. Start using
|
|
* the accepted socket. Reinitialize
|
|
* logging (since our pid has changed).
|
|
* We return from this function to handle
|
|
* the connection.
|
|
*/
|
|
platform_post_fork_child();
|
|
startup_pipe = startup_p[1];
|
|
close_startup_pipes();
|
|
close_listen_socks();
|
|
*sock_in = *newsock;
|
|
*sock_out = *newsock;
|
|
log_init(__progname,
|
|
options.log_level,
|
|
options.log_facility,
|
|
log_stderr);
|
|
if (rexec_flag)
|
|
close(config_s[0]);
|
|
else {
|
|
/*
|
|
* Signal parent that the preliminaries
|
|
* for this child are complete. For the
|
|
* re-exec case, this happens after the
|
|
* child has received the rexec state
|
|
* from the server.
|
|
*/
|
|
(void)atomicio(vwrite, startup_pipe,
|
|
"\0", 1);
|
|
}
|
|
return;
|
|
}
|
|
|
|
/* Parent. Stay in the loop. */
|
|
platform_post_fork_parent(pid);
|
|
if (pid == -1)
|
|
error("fork: %.100s", strerror(errno));
|
|
else
|
|
debug("Forked child %ld.", (long)pid);
|
|
|
|
close(startup_p[1]);
|
|
|
|
if (rexec_flag) {
|
|
close(config_s[1]);
|
|
send_rexec_state(config_s[0], cfg);
|
|
close(config_s[0]);
|
|
}
|
|
close(*newsock);
|
|
|
|
/*
|
|
* Ensure that our random state differs
|
|
* from that of the child
|
|
*/
|
|
arc4random_stir();
|
|
arc4random_buf(rnd, sizeof(rnd));
|
|
#ifdef WITH_OPENSSL
|
|
RAND_seed(rnd, sizeof(rnd));
|
|
if ((RAND_bytes((u_char *)rnd, 1)) != 1)
|
|
fatal("%s: RAND_bytes failed", __func__);
|
|
#endif
|
|
explicit_bzero(rnd, sizeof(rnd));
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If IP options are supported, make sure there are none (log and
|
|
* return an error if any are found). Basically we are worried about
|
|
* source routing; it can be used to pretend you are somebody
|
|
* (ip-address) you are not. That itself may be "almost acceptable"
|
|
* under certain circumstances, but rhosts authentication is useless
|
|
* if source routing is accepted. Notice also that if we just dropped
|
|
* source routing here, the other side could use IP spoofing to do
|
|
* rest of the interaction and could still bypass security. So we
|
|
* exit here if we detect any IP options.
|
|
*/
|
|
static void
|
|
check_ip_options(struct ssh *ssh)
|
|
{
|
|
#ifdef IP_OPTIONS
|
|
int sock_in = ssh_packet_get_connection_in(ssh);
|
|
struct sockaddr_storage from;
|
|
u_char opts[200];
|
|
socklen_t i, option_size = sizeof(opts), fromlen = sizeof(from);
|
|
char text[sizeof(opts) * 3 + 1];
|
|
|
|
memset(&from, 0, sizeof(from));
|
|
if (getpeername(sock_in, (struct sockaddr *)&from,
|
|
&fromlen) == -1)
|
|
return;
|
|
if (from.ss_family != AF_INET)
|
|
return;
|
|
/* XXX IPv6 options? */
|
|
|
|
if (getsockopt(sock_in, IPPROTO_IP, IP_OPTIONS, opts,
|
|
&option_size) >= 0 && option_size != 0) {
|
|
text[0] = '\0';
|
|
for (i = 0; i < option_size; i++)
|
|
snprintf(text + i*3, sizeof(text) - i*3,
|
|
" %2.2x", opts[i]);
|
|
fatal("Connection from %.100s port %d with IP opts: %.800s",
|
|
ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), text);
|
|
}
|
|
return;
|
|
#endif /* IP_OPTIONS */
|
|
}
|
|
|
|
/* Set the routing domain for this process */
|
|
static void
|
|
set_process_rdomain(struct ssh *ssh, const char *name)
|
|
{
|
|
#if defined(HAVE_SYS_SET_PROCESS_RDOMAIN)
|
|
if (name == NULL)
|
|
return; /* default */
|
|
|
|
if (strcmp(name, "%D") == 0) {
|
|
/* "expands" to routing domain of connection */
|
|
if ((name = ssh_packet_rdomain_in(ssh)) == NULL)
|
|
return;
|
|
}
|
|
/* NB. We don't pass 'ssh' to sys_set_process_rdomain() */
|
|
return sys_set_process_rdomain(name);
|
|
#elif defined(__OpenBSD__)
|
|
int rtable, ortable = getrtable();
|
|
const char *errstr;
|
|
|
|
if (name == NULL)
|
|
return; /* default */
|
|
|
|
if (strcmp(name, "%D") == 0) {
|
|
/* "expands" to routing domain of connection */
|
|
if ((name = ssh_packet_rdomain_in(ssh)) == NULL)
|
|
return;
|
|
}
|
|
|
|
rtable = (int)strtonum(name, 0, 255, &errstr);
|
|
if (errstr != NULL) /* Shouldn't happen */
|
|
fatal("Invalid routing domain \"%s\": %s", name, errstr);
|
|
if (rtable != ortable && setrtable(rtable) != 0)
|
|
fatal("Unable to set routing domain %d: %s",
|
|
rtable, strerror(errno));
|
|
debug_f("set routing domain %d (was %d)", rtable, ortable);
|
|
#else /* defined(__OpenBSD__) */
|
|
fatal("Unable to set routing domain: not supported in this platform");
|
|
#endif
|
|
}
|
|
|
|
static void
|
|
accumulate_host_timing_secret(struct sshbuf *server_cfg,
|
|
struct sshkey *key)
|
|
{
|
|
static struct ssh_digest_ctx *ctx;
|
|
u_char *hash;
|
|
size_t len;
|
|
struct sshbuf *buf;
|
|
int r;
|
|
|
|
if (ctx == NULL && (ctx = ssh_digest_start(SSH_DIGEST_SHA512)) == NULL)
|
|
fatal_f("ssh_digest_start");
|
|
if (key == NULL) { /* finalize */
|
|
/* add server config in case we are using agent for host keys */
|
|
if (ssh_digest_update(ctx, sshbuf_ptr(server_cfg),
|
|
sshbuf_len(server_cfg)) != 0)
|
|
fatal_f("ssh_digest_update");
|
|
len = ssh_digest_bytes(SSH_DIGEST_SHA512);
|
|
hash = xmalloc(len);
|
|
if (ssh_digest_final(ctx, hash, len) != 0)
|
|
fatal_f("ssh_digest_final");
|
|
options.timing_secret = PEEK_U64(hash);
|
|
freezero(hash, len);
|
|
ssh_digest_free(ctx);
|
|
ctx = NULL;
|
|
return;
|
|
}
|
|
if ((buf = sshbuf_new()) == NULL)
|
|
fatal_f("could not allocate buffer");
|
|
if ((r = sshkey_private_serialize(key, buf)) != 0)
|
|
fatal_fr(r, "decode key");
|
|
if (ssh_digest_update(ctx, sshbuf_ptr(buf), sshbuf_len(buf)) != 0)
|
|
fatal_f("ssh_digest_update");
|
|
sshbuf_reset(buf);
|
|
sshbuf_free(buf);
|
|
}
|
|
|
|
static char *
|
|
prepare_proctitle(int ac, char **av)
|
|
{
|
|
char *ret = NULL;
|
|
int i;
|
|
|
|
for (i = 0; i < ac; i++)
|
|
xextendf(&ret, " ", "%s", av[i]);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Main program for the daemon.
|
|
*/
|
|
int
|
|
main(int ac, char **av)
|
|
{
|
|
struct ssh *ssh = NULL;
|
|
extern char *optarg;
|
|
extern int optind;
|
|
int r, opt, on = 1, already_daemon, remote_port;
|
|
int sock_in = -1, sock_out = -1, newsock = -1;
|
|
const char *remote_ip, *rdomain;
|
|
char *fp, *line, *laddr, *logfile = NULL;
|
|
int config_s[2] = { -1 , -1 };
|
|
u_int i, j;
|
|
u_int64_t ibytes, obytes;
|
|
mode_t new_umask;
|
|
struct sshkey *key;
|
|
struct sshkey *pubkey;
|
|
int keytype;
|
|
Authctxt *authctxt;
|
|
struct connection_info *connection_info = NULL;
|
|
|
|
#ifdef HAVE_SECUREWARE
|
|
(void)set_auth_parameters(ac, av);
|
|
#endif
|
|
__progname = ssh_get_progname(av[0]);
|
|
|
|
/* Save argv. Duplicate so setproctitle emulation doesn't clobber it */
|
|
saved_argc = ac;
|
|
rexec_argc = ac;
|
|
saved_argv = xcalloc(ac + 1, sizeof(*saved_argv));
|
|
for (i = 0; (int)i < ac; i++)
|
|
saved_argv[i] = xstrdup(av[i]);
|
|
saved_argv[i] = NULL;
|
|
|
|
#ifndef HAVE_SETPROCTITLE
|
|
/* Prepare for later setproctitle emulation */
|
|
compat_init_setproctitle(ac, av);
|
|
av = saved_argv;
|
|
#endif
|
|
|
|
if (geteuid() == 0 && setgroups(0, NULL) == -1)
|
|
debug("setgroups(): %.200s", strerror(errno));
|
|
|
|
/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
|
|
sanitise_stdfd();
|
|
|
|
seed_rng();
|
|
|
|
/* Initialize configuration options to their default values. */
|
|
initialize_server_options(&options);
|
|
|
|
/* Parse command-line arguments. */
|
|
while ((opt = getopt(ac, av,
|
|
"C:E:b:c:f:g:h:k:o:p:u:46DQRTdeiqrt")) != -1) {
|
|
switch (opt) {
|
|
case '4':
|
|
options.address_family = AF_INET;
|
|
break;
|
|
case '6':
|
|
options.address_family = AF_INET6;
|
|
break;
|
|
case 'f':
|
|
config_file_name = optarg;
|
|
break;
|
|
case 'c':
|
|
servconf_add_hostcert("[command-line]", 0,
|
|
&options, optarg);
|
|
break;
|
|
case 'd':
|
|
if (debug_flag == 0) {
|
|
debug_flag = 1;
|
|
options.log_level = SYSLOG_LEVEL_DEBUG1;
|
|
} else if (options.log_level < SYSLOG_LEVEL_DEBUG3)
|
|
options.log_level++;
|
|
break;
|
|
case 'D':
|
|
no_daemon_flag = 1;
|
|
break;
|
|
case 'E':
|
|
logfile = optarg;
|
|
/* FALLTHROUGH */
|
|
case 'e':
|
|
log_stderr = 1;
|
|
break;
|
|
case 'i':
|
|
inetd_flag = 1;
|
|
break;
|
|
case 'r':
|
|
rexec_flag = 0;
|
|
break;
|
|
case 'R':
|
|
rexeced_flag = 1;
|
|
inetd_flag = 1;
|
|
break;
|
|
case 'Q':
|
|
/* ignored */
|
|
break;
|
|
case 'q':
|
|
options.log_level = SYSLOG_LEVEL_QUIET;
|
|
break;
|
|
case 'b':
|
|
/* protocol 1, ignored */
|
|
break;
|
|
case 'p':
|
|
options.ports_from_cmdline = 1;
|
|
if (options.num_ports >= MAX_PORTS) {
|
|
fprintf(stderr, "too many ports.\n");
|
|
exit(1);
|
|
}
|
|
options.ports[options.num_ports++] = a2port(optarg);
|
|
if (options.ports[options.num_ports-1] <= 0) {
|
|
fprintf(stderr, "Bad port number.\n");
|
|
exit(1);
|
|
}
|
|
break;
|
|
case 'g':
|
|
if ((options.login_grace_time = convtime(optarg)) == -1) {
|
|
fprintf(stderr, "Invalid login grace time.\n");
|
|
exit(1);
|
|
}
|
|
break;
|
|
case 'k':
|
|
/* protocol 1, ignored */
|
|
break;
|
|
case 'h':
|
|
servconf_add_hostkey("[command-line]", 0,
|
|
&options, optarg, 1);
|
|
break;
|
|
case 't':
|
|
test_flag = 1;
|
|
break;
|
|
case 'T':
|
|
test_flag = 2;
|
|
break;
|
|
case 'C':
|
|
connection_info = get_connection_info(ssh, 0, 0);
|
|
if (parse_server_match_testspec(connection_info,
|
|
optarg) == -1)
|
|
exit(1);
|
|
break;
|
|
case 'u':
|
|
utmp_len = (u_int)strtonum(optarg, 0, HOST_NAME_MAX+1+1, NULL);
|
|
if (utmp_len > HOST_NAME_MAX+1) {
|
|
fprintf(stderr, "Invalid utmp length.\n");
|
|
exit(1);
|
|
}
|
|
break;
|
|
case 'o':
|
|
line = xstrdup(optarg);
|
|
if (process_server_config_line(&options, line,
|
|
"command-line", 0, NULL, NULL, &includes) != 0)
|
|
exit(1);
|
|
free(line);
|
|
break;
|
|
case '?':
|
|
default:
|
|
usage();
|
|
break;
|
|
}
|
|
}
|
|
if (rexeced_flag || inetd_flag)
|
|
rexec_flag = 0;
|
|
if (!test_flag && rexec_flag && !path_absolute(av[0]))
|
|
fatal("sshd re-exec requires execution with an absolute path");
|
|
if (rexeced_flag)
|
|
closefrom(REEXEC_MIN_FREE_FD);
|
|
else
|
|
closefrom(REEXEC_DEVCRYPTO_RESERVED_FD);
|
|
|
|
/* If requested, redirect the logs to the specified logfile. */
|
|
if (logfile != NULL)
|
|
log_redirect_stderr_to(logfile);
|
|
/*
|
|
* Force logging to stderr until we have loaded the private host
|
|
* key (unless started from inetd)
|
|
*/
|
|
log_init(__progname,
|
|
options.log_level == SYSLOG_LEVEL_NOT_SET ?
|
|
SYSLOG_LEVEL_INFO : options.log_level,
|
|
options.log_facility == SYSLOG_FACILITY_NOT_SET ?
|
|
SYSLOG_FACILITY_AUTH : options.log_facility,
|
|
log_stderr || !inetd_flag || debug_flag);
|
|
|
|
/*
|
|
* Unset KRB5CCNAME, otherwise the user's session may inherit it from
|
|
* root's environment
|
|
*/
|
|
if (getenv("KRB5CCNAME") != NULL)
|
|
(void) unsetenv("KRB5CCNAME");
|
|
|
|
sensitive_data.have_ssh2_key = 0;
|
|
|
|
/*
|
|
* If we're not doing an extended test do not silently ignore connection
|
|
* test params.
|
|
*/
|
|
if (test_flag < 2 && connection_info != NULL)
|
|
fatal("Config test connection parameter (-C) provided without "
|
|
"test mode (-T)");
|
|
|
|
/* Fetch our configuration */
|
|
if ((cfg = sshbuf_new()) == NULL)
|
|
fatal_f("sshbuf_new failed");
|
|
if (rexeced_flag) {
|
|
setproctitle("%s", "[rexeced]");
|
|
recv_rexec_state(REEXEC_CONFIG_PASS_FD, cfg);
|
|
if (!debug_flag) {
|
|
startup_pipe = dup(REEXEC_STARTUP_PIPE_FD);
|
|
close(REEXEC_STARTUP_PIPE_FD);
|
|
/*
|
|
* Signal parent that this child is at a point where
|
|
* they can go away if they have a SIGHUP pending.
|
|
*/
|
|
(void)atomicio(vwrite, startup_pipe, "\0", 1);
|
|
}
|
|
} else if (strcasecmp(config_file_name, "none") != 0)
|
|
load_server_config(config_file_name, cfg);
|
|
|
|
parse_server_config(&options, rexeced_flag ? "rexec" : config_file_name,
|
|
cfg, &includes, NULL);
|
|
|
|
#ifdef WITH_OPENSSL
|
|
if (options.moduli_file != NULL)
|
|
dh_set_moduli_file(options.moduli_file);
|
|
#endif
|
|
|
|
/* Fill in default values for those options not explicitly set. */
|
|
fill_default_server_options(&options);
|
|
|
|
/* Check that options are sensible */
|
|
if (options.authorized_keys_command_user == NULL &&
|
|
(options.authorized_keys_command != NULL &&
|
|
strcasecmp(options.authorized_keys_command, "none") != 0))
|
|
fatal("AuthorizedKeysCommand set without "
|
|
"AuthorizedKeysCommandUser");
|
|
if (options.authorized_principals_command_user == NULL &&
|
|
(options.authorized_principals_command != NULL &&
|
|
strcasecmp(options.authorized_principals_command, "none") != 0))
|
|
fatal("AuthorizedPrincipalsCommand set without "
|
|
"AuthorizedPrincipalsCommandUser");
|
|
|
|
/*
|
|
* Check whether there is any path through configured auth methods.
|
|
* Unfortunately it is not possible to verify this generally before
|
|
* daemonisation in the presence of Match block, but this catches
|
|
* and warns for trivial misconfigurations that could break login.
|
|
*/
|
|
if (options.num_auth_methods != 0) {
|
|
for (i = 0; i < options.num_auth_methods; i++) {
|
|
if (auth2_methods_valid(options.auth_methods[i],
|
|
1) == 0)
|
|
break;
|
|
}
|
|
if (i >= options.num_auth_methods)
|
|
fatal("AuthenticationMethods cannot be satisfied by "
|
|
"enabled authentication methods");
|
|
}
|
|
|
|
/* Check that there are no remaining arguments. */
|
|
if (optind < ac) {
|
|
fprintf(stderr, "Extra argument %s.\n", av[optind]);
|
|
exit(1);
|
|
}
|
|
|
|
debug("sshd version %s, %s", SSH_VERSION, SSH_OPENSSL_VERSION);
|
|
|
|
/* Store privilege separation user for later use if required. */
|
|
privsep_chroot = use_privsep && (getuid() == 0 || geteuid() == 0);
|
|
if ((privsep_pw = getpwnam(SSH_PRIVSEP_USER)) == NULL) {
|
|
if (privsep_chroot || options.kerberos_authentication)
|
|
fatal("Privilege separation user %s does not exist",
|
|
SSH_PRIVSEP_USER);
|
|
} else {
|
|
privsep_pw = pwcopy(privsep_pw);
|
|
freezero(privsep_pw->pw_passwd, strlen(privsep_pw->pw_passwd));
|
|
privsep_pw->pw_passwd = xstrdup("*");
|
|
}
|
|
endpwent();
|
|
|
|
/* load host keys */
|
|
sensitive_data.host_keys = xcalloc(options.num_host_key_files,
|
|
sizeof(struct sshkey *));
|
|
sensitive_data.host_pubkeys = xcalloc(options.num_host_key_files,
|
|
sizeof(struct sshkey *));
|
|
|
|
if (options.host_key_agent) {
|
|
if (strcmp(options.host_key_agent, SSH_AUTHSOCKET_ENV_NAME))
|
|
setenv(SSH_AUTHSOCKET_ENV_NAME,
|
|
options.host_key_agent, 1);
|
|
if ((r = ssh_get_authentication_socket(NULL)) == 0)
|
|
have_agent = 1;
|
|
else
|
|
error_r(r, "Could not connect to agent \"%s\"",
|
|
options.host_key_agent);
|
|
}
|
|
|
|
for (i = 0; i < options.num_host_key_files; i++) {
|
|
int ll = options.host_key_file_userprovided[i] ?
|
|
SYSLOG_LEVEL_ERROR : SYSLOG_LEVEL_DEBUG1;
|
|
|
|
if (options.host_key_files[i] == NULL)
|
|
continue;
|
|
if ((r = sshkey_load_private(options.host_key_files[i], "",
|
|
&key, NULL)) != 0 && r != SSH_ERR_SYSTEM_ERROR)
|
|
do_log2_r(r, ll, "Unable to load host key \"%s\"",
|
|
options.host_key_files[i]);
|
|
if (sshkey_is_sk(key) &&
|
|
key->sk_flags & SSH_SK_USER_PRESENCE_REQD) {
|
|
debug("host key %s requires user presence, ignoring",
|
|
options.host_key_files[i]);
|
|
key->sk_flags &= ~SSH_SK_USER_PRESENCE_REQD;
|
|
}
|
|
if (r == 0 && key != NULL &&
|
|
(r = sshkey_shield_private(key)) != 0) {
|
|
do_log2_r(r, ll, "Unable to shield host key \"%s\"",
|
|
options.host_key_files[i]);
|
|
sshkey_free(key);
|
|
key = NULL;
|
|
}
|
|
if ((r = sshkey_load_public(options.host_key_files[i],
|
|
&pubkey, NULL)) != 0 && r != SSH_ERR_SYSTEM_ERROR)
|
|
do_log2_r(r, ll, "Unable to load host key \"%s\"",
|
|
options.host_key_files[i]);
|
|
if (pubkey != NULL && key != NULL) {
|
|
if (!sshkey_equal(pubkey, key)) {
|
|
error("Public key for %s does not match "
|
|
"private key", options.host_key_files[i]);
|
|
sshkey_free(pubkey);
|
|
pubkey = NULL;
|
|
}
|
|
}
|
|
if (pubkey == NULL && key != NULL) {
|
|
if ((r = sshkey_from_private(key, &pubkey)) != 0)
|
|
fatal_r(r, "Could not demote key: \"%s\"",
|
|
options.host_key_files[i]);
|
|
}
|
|
sensitive_data.host_keys[i] = key;
|
|
sensitive_data.host_pubkeys[i] = pubkey;
|
|
|
|
if (key == NULL && pubkey != NULL && have_agent) {
|
|
debug("will rely on agent for hostkey %s",
|
|
options.host_key_files[i]);
|
|
keytype = pubkey->type;
|
|
} else if (key != NULL) {
|
|
keytype = key->type;
|
|
accumulate_host_timing_secret(cfg, key);
|
|
} else {
|
|
do_log2(ll, "Unable to load host key: %s",
|
|
options.host_key_files[i]);
|
|
sensitive_data.host_keys[i] = NULL;
|
|
sensitive_data.host_pubkeys[i] = NULL;
|
|
continue;
|
|
}
|
|
|
|
switch (keytype) {
|
|
case KEY_RSA:
|
|
case KEY_DSA:
|
|
case KEY_ECDSA:
|
|
case KEY_ED25519:
|
|
case KEY_ECDSA_SK:
|
|
case KEY_ED25519_SK:
|
|
case KEY_XMSS:
|
|
if (have_agent || key != NULL)
|
|
sensitive_data.have_ssh2_key = 1;
|
|
break;
|
|
}
|
|
if ((fp = sshkey_fingerprint(pubkey, options.fingerprint_hash,
|
|
SSH_FP_DEFAULT)) == NULL)
|
|
fatal("sshkey_fingerprint failed");
|
|
debug("%s host key #%d: %s %s",
|
|
key ? "private" : "agent", i, sshkey_ssh_name(pubkey), fp);
|
|
free(fp);
|
|
}
|
|
accumulate_host_timing_secret(cfg, NULL);
|
|
if (!sensitive_data.have_ssh2_key) {
|
|
logit("sshd: no hostkeys available -- exiting.");
|
|
exit(1);
|
|
}
|
|
|
|
/*
|
|
* Load certificates. They are stored in an array at identical
|
|
* indices to the public keys that they relate to.
|
|
*/
|
|
sensitive_data.host_certificates = xcalloc(options.num_host_key_files,
|
|
sizeof(struct sshkey *));
|
|
for (i = 0; i < options.num_host_key_files; i++)
|
|
sensitive_data.host_certificates[i] = NULL;
|
|
|
|
for (i = 0; i < options.num_host_cert_files; i++) {
|
|
if (options.host_cert_files[i] == NULL)
|
|
continue;
|
|
if ((r = sshkey_load_public(options.host_cert_files[i],
|
|
&key, NULL)) != 0) {
|
|
error_r(r, "Could not load host certificate \"%s\"",
|
|
options.host_cert_files[i]);
|
|
continue;
|
|
}
|
|
if (!sshkey_is_cert(key)) {
|
|
error("Certificate file is not a certificate: %s",
|
|
options.host_cert_files[i]);
|
|
sshkey_free(key);
|
|
continue;
|
|
}
|
|
/* Find matching private key */
|
|
for (j = 0; j < options.num_host_key_files; j++) {
|
|
if (sshkey_equal_public(key,
|
|
sensitive_data.host_pubkeys[j])) {
|
|
sensitive_data.host_certificates[j] = key;
|
|
break;
|
|
}
|
|
}
|
|
if (j >= options.num_host_key_files) {
|
|
error("No matching private key for certificate: %s",
|
|
options.host_cert_files[i]);
|
|
sshkey_free(key);
|
|
continue;
|
|
}
|
|
sensitive_data.host_certificates[j] = key;
|
|
debug("host certificate: #%u type %d %s", j, key->type,
|
|
sshkey_type(key));
|
|
}
|
|
|
|
if (privsep_chroot) {
|
|
struct stat st;
|
|
|
|
if ((stat(_PATH_PRIVSEP_CHROOT_DIR, &st) == -1) ||
|
|
(S_ISDIR(st.st_mode) == 0))
|
|
fatal("Missing privilege separation directory: %s",
|
|
_PATH_PRIVSEP_CHROOT_DIR);
|
|
|
|
#ifdef HAVE_CYGWIN
|
|
if (check_ntsec(_PATH_PRIVSEP_CHROOT_DIR) &&
|
|
(st.st_uid != getuid () ||
|
|
(st.st_mode & (S_IWGRP|S_IWOTH)) != 0))
|
|
#else
|
|
if (st.st_uid != 0 || (st.st_mode & (S_IWGRP|S_IWOTH)) != 0)
|
|
#endif
|
|
fatal("%s must be owned by root and not group or "
|
|
"world-writable.", _PATH_PRIVSEP_CHROOT_DIR);
|
|
}
|
|
|
|
if (test_flag > 1) {
|
|
/*
|
|
* If no connection info was provided by -C then use
|
|
* use a blank one that will cause no predicate to match.
|
|
*/
|
|
if (connection_info == NULL)
|
|
connection_info = get_connection_info(ssh, 0, 0);
|
|
connection_info->test = 1;
|
|
parse_server_match_config(&options, &includes, connection_info);
|
|
dump_config(&options);
|
|
}
|
|
|
|
/* Configuration looks good, so exit if in test mode. */
|
|
if (test_flag)
|
|
exit(0);
|
|
|
|
/*
|
|
* Clear out any supplemental groups we may have inherited. This
|
|
* prevents inadvertent creation of files with bad modes (in the
|
|
* portable version at least, it's certainly possible for PAM
|
|
* to create a file, and we can't control the code in every
|
|
* module which might be used).
|
|
*/
|
|
if (setgroups(0, NULL) < 0)
|
|
debug("setgroups() failed: %.200s", strerror(errno));
|
|
|
|
if (rexec_flag) {
|
|
if (rexec_argc < 0)
|
|
fatal("rexec_argc %d < 0", rexec_argc);
|
|
rexec_argv = xcalloc(rexec_argc + 2, sizeof(char *));
|
|
for (i = 0; i < (u_int)rexec_argc; i++) {
|
|
debug("rexec_argv[%d]='%s'", i, saved_argv[i]);
|
|
rexec_argv[i] = saved_argv[i];
|
|
}
|
|
rexec_argv[rexec_argc] = "-R";
|
|
rexec_argv[rexec_argc + 1] = NULL;
|
|
}
|
|
listener_proctitle = prepare_proctitle(ac, av);
|
|
|
|
/* Ensure that umask disallows at least group and world write */
|
|
new_umask = umask(0077) | 0022;
|
|
(void) umask(new_umask);
|
|
|
|
/* Initialize the log (it is reinitialized below in case we forked). */
|
|
if (debug_flag && (!inetd_flag || rexeced_flag))
|
|
log_stderr = 1;
|
|
log_init(__progname, options.log_level,
|
|
options.log_facility, log_stderr);
|
|
for (i = 0; i < options.num_log_verbose; i++)
|
|
log_verbose_add(options.log_verbose[i]);
|
|
|
|
/*
|
|
* If not in debugging mode, not started from inetd and not already
|
|
* daemonized (eg re-exec via SIGHUP), disconnect from the controlling
|
|
* terminal, and fork. The original process exits.
|
|
*/
|
|
already_daemon = daemonized();
|
|
if (!(debug_flag || inetd_flag || no_daemon_flag || already_daemon)) {
|
|
|
|
if (daemon(0, 0) == -1)
|
|
fatal("daemon() failed: %.200s", strerror(errno));
|
|
|
|
disconnect_controlling_tty();
|
|
}
|
|
/* Reinitialize the log (because of the fork above). */
|
|
log_init(__progname, options.log_level, options.log_facility, log_stderr);
|
|
|
|
/* Avoid killing the process in high-pressure swapping environments. */
|
|
if (!inetd_flag && madvise(NULL, 0, MADV_PROTECT) != 0)
|
|
debug("madvise(): %.200s", strerror(errno));
|
|
|
|
/*
|
|
* Chdir to the root directory so that the current disk can be
|
|
* unmounted if desired.
|
|
*/
|
|
if (chdir("/") == -1)
|
|
error("chdir(\"/\"): %s", strerror(errno));
|
|
|
|
/* ignore SIGPIPE */
|
|
ssh_signal(SIGPIPE, SIG_IGN);
|
|
|
|
/* Get a connection, either from inetd or a listening TCP socket */
|
|
if (inetd_flag) {
|
|
server_accept_inetd(&sock_in, &sock_out);
|
|
} else {
|
|
platform_pre_listen();
|
|
server_listen();
|
|
|
|
ssh_signal(SIGHUP, sighup_handler);
|
|
ssh_signal(SIGCHLD, main_sigchld_handler);
|
|
ssh_signal(SIGTERM, sigterm_handler);
|
|
ssh_signal(SIGQUIT, sigterm_handler);
|
|
|
|
/*
|
|
* Write out the pid file after the sigterm handler
|
|
* is setup and the listen sockets are bound
|
|
*/
|
|
if (options.pid_file != NULL && !debug_flag) {
|
|
FILE *f = fopen(options.pid_file, "w");
|
|
|
|
if (f == NULL) {
|
|
error("Couldn't create pid file \"%s\": %s",
|
|
options.pid_file, strerror(errno));
|
|
} else {
|
|
fprintf(f, "%ld\n", (long) getpid());
|
|
fclose(f);
|
|
}
|
|
}
|
|
|
|
/* Accept a connection and return in a forked child */
|
|
server_accept_loop(&sock_in, &sock_out,
|
|
&newsock, config_s);
|
|
}
|
|
|
|
/* This is the child processing a new connection. */
|
|
setproctitle("%s", "[accepted]");
|
|
|
|
/*
|
|
* Create a new session and process group since the 4.4BSD
|
|
* setlogin() affects the entire process group. We don't
|
|
* want the child to be able to affect the parent.
|
|
*/
|
|
#if !defined(SSHD_ACQUIRES_CTTY)
|
|
/*
|
|
* If setsid is called, on some platforms sshd will later acquire a
|
|
* controlling terminal which will result in "could not set
|
|
* controlling tty" errors.
|
|
*/
|
|
if (!debug_flag && !inetd_flag && setsid() == -1)
|
|
error("setsid: %.100s", strerror(errno));
|
|
#endif
|
|
|
|
if (rexec_flag) {
|
|
debug("rexec start in %d out %d newsock %d pipe %d sock %d",
|
|
sock_in, sock_out, newsock, startup_pipe, config_s[0]);
|
|
dup2(newsock, STDIN_FILENO);
|
|
dup2(STDIN_FILENO, STDOUT_FILENO);
|
|
if (startup_pipe == -1)
|
|
close(REEXEC_STARTUP_PIPE_FD);
|
|
else if (startup_pipe != REEXEC_STARTUP_PIPE_FD) {
|
|
dup2(startup_pipe, REEXEC_STARTUP_PIPE_FD);
|
|
close(startup_pipe);
|
|
startup_pipe = REEXEC_STARTUP_PIPE_FD;
|
|
}
|
|
|
|
dup2(config_s[1], REEXEC_CONFIG_PASS_FD);
|
|
close(config_s[1]);
|
|
|
|
ssh_signal(SIGHUP, SIG_IGN); /* avoid reset to SIG_DFL */
|
|
execv(rexec_argv[0], rexec_argv);
|
|
|
|
/* Reexec has failed, fall back and continue */
|
|
error("rexec of %s failed: %s", rexec_argv[0], strerror(errno));
|
|
recv_rexec_state(REEXEC_CONFIG_PASS_FD, NULL);
|
|
log_init(__progname, options.log_level,
|
|
options.log_facility, log_stderr);
|
|
|
|
/* Clean up fds */
|
|
close(REEXEC_CONFIG_PASS_FD);
|
|
newsock = sock_out = sock_in = dup(STDIN_FILENO);
|
|
if (stdfd_devnull(1, 1, 0) == -1)
|
|
error_f("stdfd_devnull failed");
|
|
debug("rexec cleanup in %d out %d newsock %d pipe %d sock %d",
|
|
sock_in, sock_out, newsock, startup_pipe, config_s[0]);
|
|
}
|
|
|
|
/* Executed child processes don't need these. */
|
|
fcntl(sock_out, F_SETFD, FD_CLOEXEC);
|
|
fcntl(sock_in, F_SETFD, FD_CLOEXEC);
|
|
|
|
/* We will not restart on SIGHUP since it no longer makes sense. */
|
|
ssh_signal(SIGALRM, SIG_DFL);
|
|
ssh_signal(SIGHUP, SIG_DFL);
|
|
ssh_signal(SIGTERM, SIG_DFL);
|
|
ssh_signal(SIGQUIT, SIG_DFL);
|
|
ssh_signal(SIGCHLD, SIG_DFL);
|
|
ssh_signal(SIGINT, SIG_DFL);
|
|
|
|
#ifdef __FreeBSD__
|
|
/*
|
|
* Initialize the resolver. This may not happen automatically
|
|
* before privsep chroot().
|
|
*/
|
|
if ((_res.options & RES_INIT) == 0) {
|
|
debug("res_init()");
|
|
res_init();
|
|
}
|
|
#ifdef GSSAPI
|
|
/*
|
|
* Force GSS-API to parse its configuration and load any
|
|
* mechanism plugins.
|
|
*/
|
|
{
|
|
gss_OID_set mechs;
|
|
OM_uint32 minor_status;
|
|
gss_indicate_mechs(&minor_status, &mechs);
|
|
gss_release_oid_set(&minor_status, &mechs);
|
|
}
|
|
#endif
|
|
#endif
|
|
|
|
/*
|
|
* Register our connection. This turns encryption off because we do
|
|
* not have a key.
|
|
*/
|
|
if ((ssh = ssh_packet_set_connection(NULL, sock_in, sock_out)) == NULL)
|
|
fatal("Unable to create connection");
|
|
the_active_state = ssh;
|
|
ssh_packet_set_server(ssh);
|
|
|
|
check_ip_options(ssh);
|
|
|
|
/* Prepare the channels layer */
|
|
channel_init_channels(ssh);
|
|
channel_set_af(ssh, options.address_family);
|
|
process_permitopen(ssh, &options);
|
|
|
|
/* Set SO_KEEPALIVE if requested. */
|
|
if (options.tcp_keep_alive && ssh_packet_connection_is_on_socket(ssh) &&
|
|
setsockopt(sock_in, SOL_SOCKET, SO_KEEPALIVE, &on, sizeof(on)) == -1)
|
|
error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno));
|
|
|
|
if ((remote_port = ssh_remote_port(ssh)) < 0) {
|
|
debug("ssh_remote_port failed");
|
|
cleanup_exit(255);
|
|
}
|
|
|
|
if (options.routing_domain != NULL)
|
|
set_process_rdomain(ssh, options.routing_domain);
|
|
|
|
/*
|
|
* The rest of the code depends on the fact that
|
|
* ssh_remote_ipaddr() caches the remote ip, even if
|
|
* the socket goes away.
|
|
*/
|
|
remote_ip = ssh_remote_ipaddr(ssh);
|
|
|
|
#ifdef HAVE_LOGIN_CAP
|
|
/* Also caches remote hostname for sandboxed child. */
|
|
auth_get_canonical_hostname(ssh, options.use_dns);
|
|
#endif
|
|
|
|
#ifdef SSH_AUDIT_EVENTS
|
|
audit_connection_from(remote_ip, remote_port);
|
|
#endif
|
|
#ifdef LIBWRAP
|
|
allow_severity = options.log_facility|LOG_INFO;
|
|
deny_severity = options.log_facility|LOG_WARNING;
|
|
/* Check whether logins are denied from this host. */
|
|
if (ssh_packet_connection_is_on_socket(ssh)) {
|
|
struct request_info req;
|
|
|
|
request_init(&req, RQ_DAEMON, __progname, RQ_FILE, sock_in, 0);
|
|
fromhost(&req);
|
|
|
|
if (!hosts_access(&req)) {
|
|
debug("Connection refused by tcp wrapper");
|
|
refuse(&req);
|
|
/* NOTREACHED */
|
|
fatal("libwrap refuse returns");
|
|
}
|
|
}
|
|
#endif /* LIBWRAP */
|
|
|
|
rdomain = ssh_packet_rdomain_in(ssh);
|
|
|
|
/* Log the connection. */
|
|
laddr = get_local_ipaddr(sock_in);
|
|
verbose("Connection from %s port %d on %s port %d%s%s%s",
|
|
remote_ip, remote_port, laddr, ssh_local_port(ssh),
|
|
rdomain == NULL ? "" : " rdomain \"",
|
|
rdomain == NULL ? "" : rdomain,
|
|
rdomain == NULL ? "" : "\"");
|
|
free(laddr);
|
|
|
|
/*
|
|
* We don't want to listen forever unless the other side
|
|
* successfully authenticates itself. So we set up an alarm which is
|
|
* cleared after successful authentication. A limit of zero
|
|
* indicates no limit. Note that we don't set the alarm in debugging
|
|
* mode; it is just annoying to have the server exit just when you
|
|
* are about to discover the bug.
|
|
*/
|
|
ssh_signal(SIGALRM, grace_alarm_handler);
|
|
if (!debug_flag)
|
|
alarm(options.login_grace_time);
|
|
|
|
if ((r = kex_exchange_identification(ssh, -1,
|
|
options.version_addendum)) != 0)
|
|
sshpkt_fatal(ssh, r, "banner exchange");
|
|
|
|
ssh_packet_set_nonblocking(ssh);
|
|
|
|
/* allocate authentication context */
|
|
authctxt = xcalloc(1, sizeof(*authctxt));
|
|
ssh->authctxt = authctxt;
|
|
|
|
authctxt->loginmsg = loginmsg;
|
|
|
|
/* XXX global for cleanup, access from other modules */
|
|
the_authctxt = authctxt;
|
|
|
|
/* Set default key authentication options */
|
|
if ((auth_opts = sshauthopt_new_with_keys_defaults()) == NULL)
|
|
fatal("allocation failed");
|
|
|
|
/* prepare buffer to collect messages to display to user after login */
|
|
if ((loginmsg = sshbuf_new()) == NULL)
|
|
fatal_f("sshbuf_new failed");
|
|
auth_debug_reset();
|
|
|
|
BLACKLIST_INIT();
|
|
|
|
if (use_privsep) {
|
|
if (privsep_preauth(ssh) == 1)
|
|
goto authenticated;
|
|
} else if (have_agent) {
|
|
if ((r = ssh_get_authentication_socket(&auth_sock)) != 0) {
|
|
error_r(r, "Unable to get agent socket");
|
|
have_agent = 0;
|
|
}
|
|
}
|
|
|
|
/* perform the key exchange */
|
|
/* authenticate user and start session */
|
|
do_ssh2_kex(ssh);
|
|
do_authentication2(ssh);
|
|
|
|
/*
|
|
* If we use privilege separation, the unprivileged child transfers
|
|
* the current keystate and exits
|
|
*/
|
|
if (use_privsep) {
|
|
mm_send_keystate(ssh, pmonitor);
|
|
ssh_packet_clear_keys(ssh);
|
|
exit(0);
|
|
}
|
|
|
|
authenticated:
|
|
/*
|
|
* Cancel the alarm we set to limit the time taken for
|
|
* authentication.
|
|
*/
|
|
alarm(0);
|
|
ssh_signal(SIGALRM, SIG_DFL);
|
|
authctxt->authenticated = 1;
|
|
if (startup_pipe != -1) {
|
|
close(startup_pipe);
|
|
startup_pipe = -1;
|
|
}
|
|
|
|
#ifdef SSH_AUDIT_EVENTS
|
|
audit_event(ssh, SSH_AUTH_SUCCESS);
|
|
#endif
|
|
|
|
#ifdef GSSAPI
|
|
if (options.gss_authentication) {
|
|
temporarily_use_uid(authctxt->pw);
|
|
ssh_gssapi_storecreds();
|
|
restore_uid();
|
|
}
|
|
#endif
|
|
#ifdef USE_PAM
|
|
if (options.use_pam) {
|
|
do_pam_setcred(1);
|
|
do_pam_session(ssh);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* In privilege separation, we fork another child and prepare
|
|
* file descriptor passing.
|
|
*/
|
|
if (use_privsep) {
|
|
privsep_postauth(ssh, authctxt);
|
|
/* the monitor process [priv] will not return */
|
|
}
|
|
|
|
ssh_packet_set_timeout(ssh, options.client_alive_interval,
|
|
options.client_alive_count_max);
|
|
|
|
/* Try to send all our hostkeys to the client */
|
|
notify_hostkeys(ssh);
|
|
|
|
/* Start session. */
|
|
do_authenticated(ssh, authctxt);
|
|
|
|
/* The connection has been terminated. */
|
|
ssh_packet_get_bytes(ssh, &ibytes, &obytes);
|
|
verbose("Transferred: sent %llu, received %llu bytes",
|
|
(unsigned long long)obytes, (unsigned long long)ibytes);
|
|
|
|
verbose("Closing connection to %.500s port %d", remote_ip, remote_port);
|
|
|
|
#ifdef USE_PAM
|
|
if (options.use_pam)
|
|
finish_pam();
|
|
#endif /* USE_PAM */
|
|
|
|
#ifdef SSH_AUDIT_EVENTS
|
|
PRIVSEP(audit_event(ssh, SSH_CONNECTION_CLOSE));
|
|
#endif
|
|
|
|
ssh_packet_close(ssh);
|
|
|
|
if (use_privsep)
|
|
mm_terminate();
|
|
|
|
exit(0);
|
|
}
|
|
|
|
int
|
|
sshd_hostkey_sign(struct ssh *ssh, struct sshkey *privkey,
|
|
struct sshkey *pubkey, u_char **signature, size_t *slenp,
|
|
const u_char *data, size_t dlen, const char *alg)
|
|
{
|
|
int r;
|
|
|
|
if (use_privsep) {
|
|
if (privkey) {
|
|
if (mm_sshkey_sign(ssh, privkey, signature, slenp,
|
|
data, dlen, alg, options.sk_provider, NULL,
|
|
ssh->compat) < 0)
|
|
fatal_f("privkey sign failed");
|
|
} else {
|
|
if (mm_sshkey_sign(ssh, pubkey, signature, slenp,
|
|
data, dlen, alg, options.sk_provider, NULL,
|
|
ssh->compat) < 0)
|
|
fatal_f("pubkey sign failed");
|
|
}
|
|
} else {
|
|
if (privkey) {
|
|
if (sshkey_sign(privkey, signature, slenp, data, dlen,
|
|
alg, options.sk_provider, NULL, ssh->compat) < 0)
|
|
fatal_f("privkey sign failed");
|
|
} else {
|
|
if ((r = ssh_agent_sign(auth_sock, pubkey,
|
|
signature, slenp, data, dlen, alg,
|
|
ssh->compat)) != 0) {
|
|
fatal_fr(r, "agent sign failed");
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* SSH2 key exchange */
|
|
static void
|
|
do_ssh2_kex(struct ssh *ssh)
|
|
{
|
|
char *myproposal[PROPOSAL_MAX] = { KEX_SERVER };
|
|
struct kex *kex;
|
|
int r;
|
|
|
|
myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal(ssh,
|
|
options.kex_algorithms);
|
|
myproposal[PROPOSAL_ENC_ALGS_CTOS] = compat_cipher_proposal(ssh,
|
|
options.ciphers);
|
|
myproposal[PROPOSAL_ENC_ALGS_STOC] = compat_cipher_proposal(ssh,
|
|
options.ciphers);
|
|
myproposal[PROPOSAL_MAC_ALGS_CTOS] =
|
|
myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
|
|
|
|
if (options.compression == COMP_NONE) {
|
|
myproposal[PROPOSAL_COMP_ALGS_CTOS] =
|
|
myproposal[PROPOSAL_COMP_ALGS_STOC] = "none";
|
|
}
|
|
|
|
if (options.rekey_limit || options.rekey_interval)
|
|
ssh_packet_set_rekey_limits(ssh, options.rekey_limit,
|
|
options.rekey_interval);
|
|
|
|
myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = compat_pkalg_proposal(
|
|
ssh, list_hostkey_types());
|
|
|
|
/* start key exchange */
|
|
if ((r = kex_setup(ssh, myproposal)) != 0)
|
|
fatal_r(r, "kex_setup");
|
|
kex = ssh->kex;
|
|
#ifdef WITH_OPENSSL
|
|
kex->kex[KEX_DH_GRP1_SHA1] = kex_gen_server;
|
|
kex->kex[KEX_DH_GRP14_SHA1] = kex_gen_server;
|
|
kex->kex[KEX_DH_GRP14_SHA256] = kex_gen_server;
|
|
kex->kex[KEX_DH_GRP16_SHA512] = kex_gen_server;
|
|
kex->kex[KEX_DH_GRP18_SHA512] = kex_gen_server;
|
|
kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
|
|
kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
|
|
# ifdef OPENSSL_HAS_ECC
|
|
kex->kex[KEX_ECDH_SHA2] = kex_gen_server;
|
|
# endif
|
|
#endif
|
|
kex->kex[KEX_C25519_SHA256] = kex_gen_server;
|
|
kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_server;
|
|
kex->load_host_public_key=&get_hostkey_public_by_type;
|
|
kex->load_host_private_key=&get_hostkey_private_by_type;
|
|
kex->host_key_index=&get_hostkey_index;
|
|
kex->sign = sshd_hostkey_sign;
|
|
|
|
ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &kex->done);
|
|
|
|
#ifdef DEBUG_KEXDH
|
|
/* send 1st encrypted/maced/compressed message */
|
|
if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
|
|
(r = sshpkt_put_cstring(ssh, "markus")) != 0 ||
|
|
(r = sshpkt_send(ssh)) != 0 ||
|
|
(r = ssh_packet_write_wait(ssh)) != 0)
|
|
fatal_fr(r, "send test");
|
|
#endif
|
|
debug("KEX done");
|
|
}
|
|
|
|
/* server specific fatal cleanup */
|
|
void
|
|
cleanup_exit(int i)
|
|
{
|
|
if (the_active_state != NULL && the_authctxt != NULL) {
|
|
do_cleanup(the_active_state, the_authctxt);
|
|
if (use_privsep && privsep_is_preauth &&
|
|
pmonitor != NULL && pmonitor->m_pid > 1) {
|
|
debug("Killing privsep child %d", pmonitor->m_pid);
|
|
if (kill(pmonitor->m_pid, SIGKILL) != 0 &&
|
|
errno != ESRCH) {
|
|
error_f("kill(%d): %s", pmonitor->m_pid,
|
|
strerror(errno));
|
|
}
|
|
}
|
|
}
|
|
#ifdef SSH_AUDIT_EVENTS
|
|
/* done after do_cleanup so it can cancel the PAM auth 'thread' */
|
|
if (the_active_state != NULL && (!use_privsep || mm_is_monitor()))
|
|
audit_event(the_active_state, SSH_CONNECTION_ABANDON);
|
|
#endif
|
|
_exit(i);
|
|
}
|