838 lines
20 KiB
C
838 lines
20 KiB
C
/*-
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* Copyright (c) 1988, 1989, 1992, 1993, 1994
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* The Regents of the University of California. 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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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#ifndef lint
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static const char copyright[] =
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"@(#) Copyright (c) 1988, 1989, 1992, 1993, 1994\n\
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The Regents of the University of California. All rights reserved.\n";
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#endif /* not lint */
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#ifndef lint
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#if 0
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static const char sccsid[] = "@(#)rshd.c 8.2 (Berkeley) 4/6/94";
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#endif
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static const char rcsid[] =
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"$FreeBSD$";
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#endif /* not lint */
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/*
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* remote shell server:
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* [port]\0
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* remuser\0
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* locuser\0
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* command\0
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* data
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*/
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#include <sys/param.h>
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#include <sys/ioctl.h>
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#include <sys/time.h>
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#include <sys/socket.h>
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#include <netinet/in_systm.h>
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#include <netinet/in.h>
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#include <netinet/ip.h>
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#include <netinet/tcp.h>
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#include <arpa/inet.h>
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#include <netdb.h>
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#include <err.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <libutil.h>
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#include <paths.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 <syslog.h>
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#include <unistd.h>
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#include <login_cap.h>
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#ifdef USE_PAM
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#include <security/pam_appl.h>
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#include <sys/wait.h>
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static int export_pam_environment(void);
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static int ok_to_export(const char *);
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static pam_handle_t *pamh;
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static char **environ_pam;
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#define PAM_END { \
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if ((retcode = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS) \
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syslog(LOG_ERR|LOG_AUTH, "pam_setcred: %s", pam_strerror(pamh, retcode)); \
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if ((retcode = pam_close_session(pamh,0)) != PAM_SUCCESS) \
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syslog(LOG_ERR|LOG_AUTH, "pam_close_session: %s", pam_strerror(pamh, retcode)); \
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if ((retcode = pam_end(pamh, retcode)) != PAM_SUCCESS) \
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syslog(LOG_ERR|LOG_AUTH, "pam_end: %s", pam_strerror(pamh, retcode)); \
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}
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#endif /* USE_PAM */
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/* wrapper for KAME-special getnameinfo() */
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#ifndef NI_WITHSCOPEID
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#define NI_WITHSCOPEID 0
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#endif
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int keepalive = 1;
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int log_success; /* If TRUE, log all successful accesses */
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int sent_null;
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int no_delay;
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#ifdef CRYPT
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int doencrypt = 0;
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#endif
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union sockunion {
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struct sockinet {
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u_char si_len;
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u_char si_family;
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u_short si_port;
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} su_si;
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struct sockaddr_in su_sin;
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struct sockaddr_in6 su_sin6;
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};
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#define su_len su_si.si_len
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#define su_family su_si.si_family
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#define su_port su_si.si_port
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void doit(union sockunion *);
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static void rshd_errx(int, const char *, ...) __printf0like(2, 3);
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void getstr(char *, int, const char *);
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int local_domain(char *);
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char *topdomain(char *);
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void usage(void);
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#define OPTIONS "alnDL"
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int
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main(int argc, char *argv[])
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{
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extern int __check_rhosts_file;
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struct linger linger;
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int ch, on = 1, fromlen;
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struct sockaddr_storage from;
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openlog("rshd", LOG_PID | LOG_ODELAY, LOG_DAEMON);
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opterr = 0;
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while ((ch = getopt(argc, argv, OPTIONS)) != -1)
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switch (ch) {
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case 'a':
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/* ignored for compatibility */
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break;
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case 'l':
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__check_rhosts_file = 0;
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break;
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case 'n':
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keepalive = 0;
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break;
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#ifdef CRYPT
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case 'x':
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doencrypt = 1;
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break;
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#endif
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case 'D':
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no_delay = 1;
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break;
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case 'L':
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log_success = 1;
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break;
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case '?':
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default:
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usage();
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break;
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}
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argc -= optind;
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argv += optind;
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#ifdef CRYPT
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if (doencrypt) {
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syslog(LOG_ERR, "-k is required for -x");
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exit(2);
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}
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#endif
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fromlen = sizeof (from);
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if (getpeername(0, (struct sockaddr *)&from, &fromlen) < 0) {
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syslog(LOG_ERR, "getpeername: %m");
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exit(1);
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}
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if (keepalive &&
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setsockopt(0, SOL_SOCKET, SO_KEEPALIVE, (char *)&on,
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sizeof(on)) < 0)
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syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m");
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linger.l_onoff = 1;
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linger.l_linger = 60; /* XXX */
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if (setsockopt(0, SOL_SOCKET, SO_LINGER, (char *)&linger,
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sizeof (linger)) < 0)
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syslog(LOG_WARNING, "setsockopt (SO_LINGER): %m");
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if (no_delay &&
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setsockopt(0, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0)
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syslog(LOG_WARNING, "setsockopt (TCP_NODELAY): %m");
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doit((union sockunion *)&from);
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/* NOTREACHED */
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return(0);
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}
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#ifdef USE_PAM
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/*
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* We can't have a conversation with the client over the rsh connection.
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* You must use auth methods that don't require one, like pam_rhosts.
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*/
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static int
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null_conv(int num_msg __unused, const struct pam_message **msg __unused,
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struct pam_response **resp __unused, void *appdata_ptr __unused)
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{
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syslog(LOG_ERR, "PAM conversation is not supported");
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return PAM_CONV_ERR;
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}
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#endif /* USE_PAM */
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char username[20] = "USER=";
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char homedir[64] = "HOME=";
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char shell[64] = "SHELL=";
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char path[100] = "PATH=";
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char *envinit[] =
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{homedir, shell, path, username, 0};
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char **environ;
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void
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doit(union sockunion *fromp)
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{
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extern char *__rcmd_errstr; /* syslog hook from libc/net/rcmd.c. */
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struct passwd *pwd;
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u_short port;
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fd_set ready, readfrom;
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int cc, nfd, pv[2], pid, s;
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int one = 1;
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const char *errorstr;
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char *cp, sig, buf[BUFSIZ];
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char cmdbuf[NCARGS+1], locuser[16], remuser[16];
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char fromhost[2 * MAXHOSTNAMELEN + 1];
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char numericname[INET6_ADDRSTRLEN];
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int af = fromp->su_family, error;
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#ifdef CRYPT
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int rc;
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int pv1[2], pv2[2];
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#endif
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login_cap_t *lc;
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#ifdef USE_PAM
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static struct pam_conv conv = { null_conv, NULL };
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int retcode;
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#endif /* USE_PAM */
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(void) signal(SIGINT, SIG_DFL);
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(void) signal(SIGQUIT, SIG_DFL);
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(void) signal(SIGTERM, SIG_DFL);
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fromp->su_port = ntohs((u_short)fromp->su_port);
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if (af != AF_INET
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#ifdef INET6
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&& af != AF_INET6
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#endif
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) {
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syslog(LOG_ERR, "malformed \"from\" address (af %d)", af);
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exit(1);
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}
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error = getnameinfo((struct sockaddr *)fromp, fromp->su_len,
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numericname, sizeof(numericname), NULL, 0,
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NI_NUMERICHOST|NI_WITHSCOPEID);
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/* XXX: do 'error' check */
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#ifdef IP_OPTIONS
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if (af == AF_INET) {
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u_char optbuf[BUFSIZ/3];
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int optsize = sizeof(optbuf), ipproto, i;
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struct protoent *ip;
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if ((ip = getprotobyname("ip")) != NULL)
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ipproto = ip->p_proto;
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else
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ipproto = IPPROTO_IP;
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if (!getsockopt(0, ipproto, IP_OPTIONS, (char *)optbuf, &optsize) &&
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optsize != 0) {
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for (i = 0; i < optsize; ) {
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u_char c = optbuf[i];
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if (c == IPOPT_LSRR || c == IPOPT_SSRR) {
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syslog(LOG_NOTICE,
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"connection refused from %s with IP option %s",
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numericname,
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c == IPOPT_LSRR ? "LSRR" : "SSRR");
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exit(1);
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}
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if (c == IPOPT_EOL)
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break;
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i += (c == IPOPT_NOP) ? 1 : optbuf[i+1];
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}
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}
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}
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#endif
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if (fromp->su_port >= IPPORT_RESERVED ||
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fromp->su_port < IPPORT_RESERVED/2) {
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syslog(LOG_NOTICE|LOG_AUTH,
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"connection from %s on illegal port %u",
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numericname,
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fromp->su_port);
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exit(1);
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}
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(void) alarm(60);
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port = 0;
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s = 0; /* not set or used if port == 0 */
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for (;;) {
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char c;
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if ((cc = read(STDIN_FILENO, &c, 1)) != 1) {
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if (cc < 0)
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syslog(LOG_NOTICE, "read: %m");
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shutdown(0, 1+1);
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exit(1);
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}
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if (c == 0)
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break;
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port = port * 10 + c - '0';
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}
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(void) alarm(0);
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if (port != 0) {
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int lport = IPPORT_RESERVED - 1;
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s = rresvport_af(&lport, af);
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if (s < 0) {
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syslog(LOG_ERR, "can't get stderr port: %m");
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exit(1);
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}
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if (port >= IPPORT_RESERVED ||
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port < IPPORT_RESERVED/2) {
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syslog(LOG_NOTICE|LOG_AUTH,
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"2nd socket from %s on unreserved port %u",
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numericname,
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port);
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exit(1);
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}
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fromp->su_port = htons(port);
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if (connect(s, (struct sockaddr *)fromp, fromp->su_len) < 0) {
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syslog(LOG_INFO, "connect second port %d: %m", port);
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exit(1);
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}
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}
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errorstr = NULL;
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realhostname_sa(fromhost, sizeof(fromhost) - 1,
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(struct sockaddr *)fromp,
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fromp->su_len);
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fromhost[sizeof(fromhost) - 1] = '\0';
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#ifdef CRYPT
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if (doencrypt && af == AF_INET) {
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struct sockaddr_in local_addr;
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rc = sizeof(local_addr);
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if (getsockname(0, (struct sockaddr *)&local_addr,
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&rc) < 0) {
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syslog(LOG_ERR, "getsockname: %m");
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rshd_errx(1, "rlogind: getsockname: %m"); /* XXX */
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}
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authopts = KOPT_DO_MUTUAL;
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rc = krb_recvauth(authopts, 0, ticket,
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"rcmd", instance, &fromaddr,
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&local_addr, kdata, "", schedule,
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version);
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des_set_key(&kdata->session, schedule);
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}
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#endif
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getstr(remuser, sizeof(remuser), "remuser");
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getstr(locuser, sizeof(locuser), "locuser");
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getstr(cmdbuf, sizeof(cmdbuf), "command");
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#ifdef USE_PAM
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retcode = pam_start("rsh", locuser, &conv, &pamh);
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if (retcode != PAM_SUCCESS) {
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syslog(LOG_ERR|LOG_AUTH, "pam_start: %s", pam_strerror(pamh, retcode));
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rshd_errx(1, "Login incorrect.");
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}
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retcode = pam_set_item (pamh, PAM_RUSER, remuser);
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if (retcode != PAM_SUCCESS) {
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syslog(LOG_ERR|LOG_AUTH, "pam_set_item(PAM_RUSER): %s", pam_strerror(pamh, retcode));
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rshd_errx(1, "Login incorrect.");
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}
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retcode = pam_set_item (pamh, PAM_RHOST, fromhost);
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if (retcode != PAM_SUCCESS) {
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syslog(LOG_ERR|LOG_AUTH, "pam_set_item(PAM_RHOST): %s", pam_strerror(pamh, retcode));
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rshd_errx(1, "Login incorrect.");
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}
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retcode = pam_set_item (pamh, PAM_TTY, "tty");
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if (retcode != PAM_SUCCESS) {
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syslog(LOG_ERR|LOG_AUTH, "pam_set_item(PAM_TTY): %s", pam_strerror(pamh, retcode));
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rshd_errx(1, "Login incorrect.");
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}
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retcode = pam_authenticate(pamh, 0);
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if (retcode == PAM_SUCCESS) {
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if ((retcode = pam_get_item(pamh, PAM_USER, (const void **) &cp)) == PAM_SUCCESS) {
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strncpy(locuser, cp, sizeof(locuser));
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locuser[sizeof(locuser) - 1] = '\0';
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} else
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syslog(LOG_ERR|LOG_AUTH, "pam_get_item(PAM_USER): %s",
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pam_strerror(pamh, retcode));
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retcode = pam_acct_mgmt(pamh, 0);
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}
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if (retcode != PAM_SUCCESS) {
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syslog(LOG_INFO|LOG_AUTH, "%s@%s as %s: permission denied (%s). cmd='%.80s'",
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remuser, fromhost, locuser, pam_strerror(pamh, retcode), cmdbuf);
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rshd_errx(1, "Login incorrect.");
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}
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#endif /* USE_PAM */
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setpwent();
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pwd = getpwnam(locuser);
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if (pwd == NULL) {
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syslog(LOG_INFO|LOG_AUTH,
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"%s@%s as %s: unknown login. cmd='%.80s'",
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remuser, fromhost, locuser, cmdbuf);
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if (errorstr == NULL)
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errorstr = "Login incorrect.";
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rshd_errx(1, errorstr, fromhost);
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}
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#ifndef USE_PAM
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if (errorstr ||
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(pwd->pw_expire && time(NULL) >= pwd->pw_expire) ||
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iruserok_sa(fromp, fromp->su_len, pwd->pw_uid == 0,
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remuser, locuser) < 0) {
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if (__rcmd_errstr)
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syslog(LOG_INFO|LOG_AUTH,
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"%s@%s as %s: permission denied (%s). cmd='%.80s'",
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remuser, fromhost, locuser, __rcmd_errstr,
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cmdbuf);
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else
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syslog(LOG_INFO|LOG_AUTH,
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"%s@%s as %s: permission denied. cmd='%.80s'",
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remuser, fromhost, locuser, cmdbuf);
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if (errorstr == NULL)
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errorstr = "Login incorrect.";
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rshd_errx(1, errorstr, fromhost);
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}
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#endif /* USE_PAM */
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lc = login_getpwclass(pwd);
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if (pwd->pw_uid)
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auth_checknologin(lc);
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if (chdir(pwd->pw_dir) < 0) {
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if (chdir("/") < 0 ||
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login_getcapbool(lc, "requirehome", !!pwd->pw_uid)) {
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syslog(LOG_INFO|LOG_AUTH,
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"%s@%s as %s: no home directory. cmd='%.80s'",
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remuser, fromhost, locuser, cmdbuf);
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rshd_errx(0, "No remote home directory.");
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}
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pwd->pw_dir = "/";
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}
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if (lc != NULL && fromp->su_family == AF_INET) { /*XXX*/
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char remote_ip[MAXHOSTNAMELEN];
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strncpy(remote_ip, numericname,
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sizeof(remote_ip) - 1);
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remote_ip[sizeof(remote_ip) - 1] = 0;
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if (!auth_hostok(lc, fromhost, remote_ip)) {
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syslog(LOG_INFO|LOG_AUTH,
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"%s@%s as %s: permission denied (%s). cmd='%.80s'",
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remuser, fromhost, locuser, __rcmd_errstr,
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cmdbuf);
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rshd_errx(1, "Login incorrect.");
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}
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if (!auth_timeok(lc, time(NULL)))
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rshd_errx(1, "Logins not available right now");
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}
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#if BSD > 43
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/* before fork, while we're session leader */
|
|
if (setlogin(pwd->pw_name) < 0)
|
|
syslog(LOG_ERR, "setlogin() failed: %m");
|
|
#endif
|
|
|
|
/*
|
|
* PAM modules might add supplementary groups in
|
|
* pam_setcred(), so initialize them first.
|
|
* But we need to open the session as root.
|
|
*/
|
|
if (setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETGROUP) != 0) {
|
|
syslog(LOG_ERR, "setusercontext: %m");
|
|
exit(1);
|
|
}
|
|
|
|
#ifdef USE_PAM
|
|
if ((retcode = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
|
|
syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, retcode));
|
|
} else if ((retcode = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
|
|
syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, retcode));
|
|
}
|
|
#endif /* USE_PAM */
|
|
|
|
(void) write(STDERR_FILENO, "\0", 1);
|
|
sent_null = 1;
|
|
|
|
if (port) {
|
|
if (pipe(pv) < 0)
|
|
rshd_errx(1, "Can't make pipe.");
|
|
#ifdef CRYPT
|
|
if (doencrypt) {
|
|
if (pipe(pv1) < 0)
|
|
rshd_errx(1, "Can't make 2nd pipe.");
|
|
if (pipe(pv2) < 0)
|
|
rshd_errx(1, "Can't make 3rd pipe.");
|
|
}
|
|
#endif
|
|
pid = fork();
|
|
if (pid == -1)
|
|
rshd_errx(1, "Can't fork; try again.");
|
|
if (pid) {
|
|
#ifdef CRYPT
|
|
if (doencrypt) {
|
|
static char msg[] = SECURE_MESSAGE;
|
|
(void) close(pv1[1]);
|
|
(void) close(pv2[1]);
|
|
des_enc_write(s, msg, sizeof(msg) - 1,
|
|
schedule, &kdata->session);
|
|
|
|
} else
|
|
#endif
|
|
{
|
|
(void) close(0);
|
|
(void) close(1);
|
|
}
|
|
(void) close(2);
|
|
(void) close(pv[1]);
|
|
|
|
FD_ZERO(&readfrom);
|
|
FD_SET(s, &readfrom);
|
|
FD_SET(pv[0], &readfrom);
|
|
if (pv[0] > s)
|
|
nfd = pv[0];
|
|
else
|
|
nfd = s;
|
|
#ifdef CRYPT
|
|
if (doencrypt) {
|
|
FD_ZERO(&writeto);
|
|
FD_SET(pv2[0], &writeto);
|
|
FD_SET(pv1[0], &readfrom);
|
|
|
|
nfd = MAX(nfd, pv2[0]);
|
|
nfd = MAX(nfd, pv1[0]);
|
|
} else
|
|
#endif
|
|
ioctl(pv[0], FIONBIO, (char *)&one);
|
|
|
|
/* should set s nbio! */
|
|
nfd++;
|
|
do {
|
|
ready = readfrom;
|
|
#ifdef CRYPT
|
|
if (doencrypt) {
|
|
wready = writeto;
|
|
if (select(nfd, &ready,
|
|
&wready, (fd_set *) 0,
|
|
(struct timeval *) 0) < 0)
|
|
break;
|
|
} else
|
|
#endif
|
|
if (select(nfd, &ready, (fd_set *)0,
|
|
(fd_set *)0, (struct timeval *)0) < 0)
|
|
break;
|
|
if (FD_ISSET(s, &ready)) {
|
|
int ret;
|
|
#ifdef CRYPT
|
|
if (doencrypt)
|
|
ret = des_enc_read(s, &sig, 1,
|
|
schedule, &kdata->session);
|
|
else
|
|
#endif
|
|
ret = read(s, &sig, 1);
|
|
if (ret <= 0)
|
|
FD_CLR(s, &readfrom);
|
|
else
|
|
killpg(pid, sig);
|
|
}
|
|
if (FD_ISSET(pv[0], &ready)) {
|
|
errno = 0;
|
|
cc = read(pv[0], buf, sizeof(buf));
|
|
if (cc <= 0) {
|
|
shutdown(s, 1+1);
|
|
FD_CLR(pv[0], &readfrom);
|
|
} else {
|
|
#ifdef CRYPT
|
|
if (doencrypt)
|
|
(void)
|
|
des_enc_write(s, buf, cc,
|
|
schedule, &kdata->session);
|
|
else
|
|
#endif
|
|
(void)
|
|
write(s, buf, cc);
|
|
}
|
|
}
|
|
#ifdef CRYPT
|
|
if (doencrypt && FD_ISSET(pv1[0], &ready)) {
|
|
errno = 0;
|
|
cc = read(pv1[0], buf, sizeof(buf));
|
|
if (cc <= 0) {
|
|
shutdown(pv1[0], 1+1);
|
|
FD_CLR(pv1[0], &readfrom);
|
|
} else
|
|
(void) des_enc_write(STDOUT_FILENO,
|
|
buf, cc,
|
|
schedule, &kdata->session);
|
|
}
|
|
|
|
if (doencrypt && FD_ISSET(pv2[0], &wready)) {
|
|
errno = 0;
|
|
cc = des_enc_read(STDIN_FILENO,
|
|
buf, sizeof(buf),
|
|
schedule, &kdata->session);
|
|
if (cc <= 0) {
|
|
shutdown(pv2[0], 1+1);
|
|
FD_CLR(pv2[0], &writeto);
|
|
} else
|
|
(void) write(pv2[0], buf, cc);
|
|
}
|
|
#endif
|
|
|
|
} while (FD_ISSET(s, &readfrom) ||
|
|
#ifdef CRYPT
|
|
(doencrypt && FD_ISSET(pv1[0], &readfrom)) ||
|
|
#endif
|
|
FD_ISSET(pv[0], &readfrom));
|
|
#ifdef USE_PAM
|
|
PAM_END;
|
|
#endif /* USE_PAM */
|
|
exit(0);
|
|
}
|
|
setpgrp(0, getpid());
|
|
(void) close(s);
|
|
(void) close(pv[0]);
|
|
#ifdef CRYPT
|
|
if (doencrypt) {
|
|
close(pv1[0]); close(pv2[0]);
|
|
dup2(pv1[1], 1);
|
|
dup2(pv2[1], 0);
|
|
close(pv1[1]);
|
|
close(pv2[1]);
|
|
}
|
|
#endif
|
|
dup2(pv[1], 2);
|
|
close(pv[1]);
|
|
}
|
|
#ifdef USE_PAM
|
|
else {
|
|
pid = fork();
|
|
if (pid == -1)
|
|
rshd_errx(1, "Can't fork; try again.");
|
|
if (pid) {
|
|
/* Parent. */
|
|
wait(NULL);
|
|
PAM_END;
|
|
exit(0);
|
|
}
|
|
}
|
|
#endif /* USE_PAM */
|
|
|
|
if (*pwd->pw_shell == '\0')
|
|
pwd->pw_shell = _PATH_BSHELL;
|
|
environ = envinit;
|
|
|
|
#ifdef USE_PAM
|
|
/*
|
|
* Add any environmental variables that the
|
|
* PAM modules may have set.
|
|
*/
|
|
environ_pam = pam_getenvlist(pamh);
|
|
if (environ_pam)
|
|
export_pam_environment();
|
|
if ((retcode = pam_end(pamh, PAM_DATA_SILENT)) != PAM_SUCCESS)
|
|
syslog(LOG_ERR|LOG_AUTH, "pam_end: %s", pam_strerror(pamh, retcode));
|
|
#endif /* USE_PAM */
|
|
|
|
strncat(homedir, pwd->pw_dir, sizeof(homedir)-6);
|
|
strcat(path, _PATH_DEFPATH);
|
|
strncat(shell, pwd->pw_shell, sizeof(shell)-7);
|
|
strncat(username, pwd->pw_name, sizeof(username)-6);
|
|
cp = strrchr(pwd->pw_shell, '/');
|
|
if (cp)
|
|
cp++;
|
|
else
|
|
cp = pwd->pw_shell;
|
|
|
|
if (setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETALL & ~LOGIN_SETGROUP) != 0) {
|
|
syslog(LOG_ERR, "setusercontext: %m");
|
|
exit(1);
|
|
}
|
|
login_close(lc);
|
|
|
|
endpwent();
|
|
if (log_success || pwd->pw_uid == 0) {
|
|
syslog(LOG_INFO|LOG_AUTH, "%s@%s as %s: cmd='%.80s'",
|
|
remuser, fromhost, locuser, cmdbuf);
|
|
}
|
|
execl(pwd->pw_shell, cp, "-c", cmdbuf, (char *)0);
|
|
perror(pwd->pw_shell);
|
|
exit(1);
|
|
}
|
|
|
|
/*
|
|
* Report error to client. Note: can't be used until second socket has
|
|
* connected to client, or older clients will hang waiting for that
|
|
* connection first.
|
|
*/
|
|
|
|
static void
|
|
rshd_errx(int errcode, const char *fmt, ...)
|
|
{
|
|
va_list ap;
|
|
|
|
va_start(ap, fmt);
|
|
|
|
if (sent_null == 0)
|
|
write(STDERR_FILENO, "\1", 1);
|
|
|
|
verrx(errcode, fmt, ap);
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
void
|
|
getstr(char *buf, int cnt, const char *error)
|
|
{
|
|
char c;
|
|
|
|
do {
|
|
if (read(STDIN_FILENO, &c, 1) != 1)
|
|
exit(1);
|
|
*buf++ = c;
|
|
if (--cnt == 0)
|
|
rshd_errx(1, "%s too long", error);
|
|
} while (c != 0);
|
|
}
|
|
|
|
/*
|
|
* Check whether host h is in our local domain,
|
|
* defined as sharing the last two components of the domain part,
|
|
* or the entire domain part if the local domain has only one component.
|
|
* If either name is unqualified (contains no '.'),
|
|
* assume that the host is local, as it will be
|
|
* interpreted as such.
|
|
*/
|
|
int
|
|
local_domain(char *h)
|
|
{
|
|
char localhost[MAXHOSTNAMELEN];
|
|
char *p1, *p2;
|
|
|
|
localhost[0] = 0;
|
|
(void) gethostname(localhost, sizeof(localhost) - 1);
|
|
localhost[sizeof(localhost) - 1] = '\0';
|
|
p1 = topdomain(localhost);
|
|
p2 = topdomain(h);
|
|
if (p1 == NULL || p2 == NULL || !strcasecmp(p1, p2))
|
|
return (1);
|
|
return (0);
|
|
}
|
|
|
|
char *
|
|
topdomain(char *h)
|
|
{
|
|
char *p, *maybe = NULL;
|
|
int dots = 0;
|
|
|
|
for (p = h + strlen(h); p >= h; p--) {
|
|
if (*p == '.') {
|
|
if (++dots == 2)
|
|
return (p);
|
|
maybe = p;
|
|
}
|
|
}
|
|
return (maybe);
|
|
}
|
|
|
|
#ifdef USE_PAM
|
|
static int
|
|
export_pam_environment(void)
|
|
{
|
|
char **pp;
|
|
|
|
for (pp = environ_pam; *pp != NULL; pp++) {
|
|
if (ok_to_export(*pp))
|
|
(void) putenv(*pp);
|
|
free(*pp);
|
|
}
|
|
return PAM_SUCCESS;
|
|
}
|
|
|
|
/*
|
|
* Sanity checks on PAM environmental variables:
|
|
* - Make sure there is an '=' in the string.
|
|
* - Make sure the string doesn't run on too long.
|
|
* - Do not export certain variables. This list was taken from the
|
|
* Solaris pam_putenv(3) man page.
|
|
*/
|
|
static int
|
|
ok_to_export(const char *s)
|
|
{
|
|
static const char *noexport[] = {
|
|
"SHELL", "HOME", "LOGNAME", "MAIL", "CDPATH",
|
|
"IFS", "PATH", NULL
|
|
};
|
|
const char **pp;
|
|
size_t n;
|
|
|
|
if (strlen(s) > 1024 || strchr(s, '=') == NULL)
|
|
return 0;
|
|
if (strncmp(s, "LD_", 3) == 0)
|
|
return 0;
|
|
for (pp = noexport; *pp != NULL; pp++) {
|
|
n = strlen(*pp);
|
|
if (s[n] == '=' && strncmp(s, *pp, n) == 0)
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
#endif /* USE_PAM */
|
|
|
|
void
|
|
usage(void)
|
|
{
|
|
|
|
syslog(LOG_ERR, "usage: rshd [-%s]", OPTIONS);
|
|
exit(2);
|
|
}
|