810 lines
22 KiB
C
810 lines
22 KiB
C
/* $NetBSD: rshd.c,v 1.50 2012/07/14 15:06:26 darrenr Exp $ */
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/*
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* Copyright (C) 1998 WIDE Project.
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* 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 WIDE Project and
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* its contributors.
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* 4. Neither the name of the project 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 PROJECT 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 PROJECT 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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/*-
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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. 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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#include <sys/cdefs.h>
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#ifndef lint
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__COPYRIGHT("@(#) 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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#if 0
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static char sccsid[] = "@(#)rshd.c 8.2 (Berkeley) 4/6/94";
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#else
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__RCSID("$NetBSD: rshd.c,v 1.50 2012/07/14 15:06:26 darrenr Exp $");
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#endif
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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 <errno.h>
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#include <fcntl.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 <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 <poll.h>
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#ifdef LOGIN_CAP
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#include <login_cap.h>
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#endif
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#ifdef USE_PAM
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#include <security/pam_appl.h>
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#include <security/openpam.h>
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#include <sys/wait.h>
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static struct pam_conv pamc = { openpam_nullconv, NULL };
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static pam_handle_t *pamh;
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static int pam_err;
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#define PAM_END do { \
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if ((pam_err = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS) \
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syslog(LOG_ERR|LOG_AUTH, "pam_setcred(): %s", \
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pam_strerror(pamh, pam_err)); \
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if ((pam_err = pam_close_session(pamh,0)) != PAM_SUCCESS) \
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syslog(LOG_ERR|LOG_AUTH, "pam_close_session(): %s", \
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pam_strerror(pamh, pam_err)); \
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if ((pam_err = pam_end(pamh, pam_err)) != PAM_SUCCESS) \
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syslog(LOG_ERR|LOG_AUTH, "pam_end(): %s", \
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pam_strerror(pamh, pam_err)); \
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} while (/*CONSTCOND*/0)
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#else
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#define PAM_END
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#endif
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static int keepalive = 1;
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static int check_all;
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static int log_success; /* If TRUE, log all successful accesses */
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static int sent_null;
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__dead static void doit(struct sockaddr *, struct sockaddr *);
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__dead static void rshd_errx(int, const char *, ...) __printflike(2, 3);
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static void getstr(char *, int, const char *);
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static int local_domain(char *);
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static char *topdomain(char *);
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__dead static void usage(void);
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#define OPTIONS "aLln"
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extern int __check_rhosts_file;
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extern char *__rcmd_errstr; /* syslog hook from libc/net/rcmd.c. */
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#ifdef USE_PAM
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static const char incorrect[] = "Login incorrect.";
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#endif
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int
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main(int argc, char *argv[])
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{
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struct linger linger;
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int ch, on = 1;
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socklen_t fromlen;
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socklen_t locallen;
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struct sockaddr_storage from;
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struct sockaddr_storage local;
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struct protoent *proto;
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openlog("rshd", LOG_PID, 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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check_all = 1;
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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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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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fromlen = sizeof(from); /* xxx */
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locallen = sizeof(local); /* xxx */
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if (getpeername(STDIN_FILENO, (struct sockaddr *)&from, &fromlen) < 0) {
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syslog(LOG_ERR, "getpeername: %m");
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return EXIT_FAILURE;
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}
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if (getsockname(STDIN_FILENO, (struct sockaddr *)&local,
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&locallen) < 0) {
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syslog(LOG_ERR, "getsockname: %m");
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return EXIT_FAILURE;
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}
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#if 0
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if (((struct sockaddr *)&from)->sa_family == AF_INET6 &&
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IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&from)->sin6_addr) &&
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sizeof(struct sockaddr_in) <= sizeof(from)) {
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struct sockaddr_in sin;
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struct sockaddr_in6 *sin6;
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const int off = sizeof(struct sockaddr_in6) -
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sizeof(struct sockaddr_in);
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sin6 = (struct sockaddr_in6 *)&from;
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(void)memset(&sin, 0, sizeof(sin));
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sin.sin_family = AF_INET;
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sin.sin_len = sizeof(struct sockaddr_in);
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(void)memcpy(&sin.sin_addr, &sin6->sin6_addr.s6_addr[off],
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sizeof(sin.sin_addr));
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(void)memcpy(&from, &sin, sizeof(sin));
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fromlen = sin.sin_len;
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}
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#else
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if (((struct sockaddr *)&from)->sa_family == AF_INET6 &&
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IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&from)->sin6_addr)) {
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char hbuf[NI_MAXHOST];
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if (getnameinfo((struct sockaddr *)&from, fromlen, hbuf,
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sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0) {
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strlcpy(hbuf, "invalid", sizeof(hbuf));
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}
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syslog(LOG_ERR, "malformed \"from\" address (v4 mapped, %s)",
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hbuf);
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return EXIT_FAILURE;
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}
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#endif
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if (keepalive &&
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setsockopt(STDIN_FILENO, 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(STDIN_FILENO, 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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proto = getprotobyname("tcp");
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(void)setsockopt(STDIN_FILENO, proto->p_proto, TCP_NODELAY, &on,
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sizeof(on));
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doit((struct sockaddr *)&from, (struct sockaddr *)&local);
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}
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extern char **environ;
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static void
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doit(struct sockaddr *fromp, struct sockaddr *localp)
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{
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struct passwd *pwd, pwres;
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in_port_t port;
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struct pollfd set[2];
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int cc, pv[2], pid, s = -1; /* XXX gcc */
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int one = 1;
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char *hostname, *errorhost = NULL; /* XXX gcc */
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const char *cp;
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char sig, buf[BUFSIZ];
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char cmdbuf[NCARGS+1], locuser[16], remuser[16];
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char remotehost[2 * MAXHOSTNAMELEN + 1];
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char hostnamebuf[2 * MAXHOSTNAMELEN + 1];
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#ifdef LOGIN_CAP
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login_cap_t *lc;
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#endif
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char naddr[NI_MAXHOST];
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char saddr[NI_MAXHOST];
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char raddr[NI_MAXHOST];
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char pbuf[NI_MAXSERV];
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int af = fromp->sa_family;
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u_int16_t *portp;
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struct addrinfo hints, *res, *res0;
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int gaierror;
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const int niflags = NI_NUMERICHOST | NI_NUMERICSERV;
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const char *errormsg = NULL, *errorstr = NULL;
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char pwbuf[1024];
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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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#ifdef DEBUG
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{
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int t = open(_PATH_TTY, O_RDWR);
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if (t >= 0) {
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ioctl(t, TIOCNOTTY, NULL);
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(void)close(t);
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}
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}
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#endif
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switch (af) {
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case AF_INET:
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portp = &((struct sockaddr_in *)fromp)->sin_port;
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break;
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#ifdef INET6
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case AF_INET6:
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portp = &((struct sockaddr_in6 *)fromp)->sin6_port;
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break;
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#endif
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default:
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syslog(LOG_ERR, "malformed \"from\" address (af %d)", af);
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exit(EXIT_FAILURE);
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}
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if (getnameinfo(fromp, fromp->sa_len, naddr, sizeof(naddr),
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pbuf, sizeof(pbuf), niflags) != 0) {
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syslog(LOG_ERR, "malformed \"from\" address (af %d)", af);
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exit(EXIT_FAILURE);
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}
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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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socklen_t optsize = sizeof(optbuf);
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int ipproto;
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unsigned int 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 "
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"with IP option %s",
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inet_ntoa((
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(struct sockaddr_in *)fromp)->sin_addr),
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c == IPOPT_LSRR ? "LSRR" : "SSRR");
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exit(EXIT_FAILURE);
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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 (ntohs(*portp) >= IPPORT_RESERVED
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|| ntohs(*portp) < 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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naddr, ntohs(*portp));
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exit(EXIT_FAILURE);
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}
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(void) alarm(60);
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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_ERR, "read: %m");
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(void)shutdown(0, SHUT_RDWR);
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exit(EXIT_FAILURE);
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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_addr(&lport, af, localp);
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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(EXIT_FAILURE);
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}
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if (port >= IPPORT_RESERVED) {
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syslog(LOG_ERR, "2nd port not reserved");
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exit(EXIT_FAILURE);
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}
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*portp = htons(port);
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if (connect(s, fromp, fromp->sa_len) < 0) {
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syslog(LOG_ERR, "connect second port %d: %m", port);
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exit(EXIT_FAILURE);
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}
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}
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#ifdef notdef
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/* from inetd, socket is already on 0, 1, 2 */
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(void)dup2(f, STDIN_FILENO);
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(void)dup2(f, STDOUT_FILENO);
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(void)dup2(f, STDERR_FILENO);
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#endif
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if (getnameinfo(fromp, fromp->sa_len, saddr, sizeof(saddr),
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NULL, 0, NI_NAMEREQD) == 0) {
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/*
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* If name returned by getnameinfo is in our domain,
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* attempt to verify that we haven't been fooled by someone
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* in a remote net; look up the name and check that this
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* address corresponds to the name.
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*/
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hostname = saddr;
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res0 = NULL;
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if (check_all || local_domain(saddr)) {
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(void)strlcpy(remotehost, saddr, sizeof(remotehost));
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errorhost = remotehost;
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(void)memset(&hints, 0, sizeof(hints));
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hints.ai_family = fromp->sa_family;
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hints.ai_socktype = SOCK_STREAM;
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hints.ai_flags = AI_CANONNAME;
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gaierror = getaddrinfo(remotehost, pbuf, &hints, &res0);
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if (gaierror) {
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syslog(LOG_NOTICE,
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"Couldn't look up address for %s: %s",
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remotehost, gai_strerror(gaierror));
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errorstr =
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"Couldn't look up address for your host (%s)\n";
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hostname = naddr;
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} else {
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for (res = res0; res; res = res->ai_next) {
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if (res->ai_family != fromp->sa_family)
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continue;
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if (res->ai_addrlen != fromp->sa_len)
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continue;
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if (getnameinfo(res->ai_addr,
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res->ai_addrlen,
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raddr, sizeof(raddr), NULL, 0,
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niflags) == 0
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&& strcmp(naddr, raddr) == 0) {
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hostname = res->ai_canonname
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? res->ai_canonname
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: saddr;
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break;
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}
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}
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if (res == NULL) {
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syslog(LOG_NOTICE,
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"Host addr %s not listed for host %s",
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naddr, res0->ai_canonname
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? res0->ai_canonname
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: saddr);
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errorstr =
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"Host address mismatch for %s\n";
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hostname = naddr;
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}
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}
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}
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(void)strlcpy(hostnamebuf, hostname, sizeof(hostnamebuf));
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hostname = hostnamebuf;
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if (res0)
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freeaddrinfo(res0);
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} else {
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(void)strlcpy(hostnamebuf, naddr, sizeof(hostnamebuf));
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errorhost = hostname = hostnamebuf;
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}
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(void)alarm(60);
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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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(void)alarm(0);
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#ifdef USE_PAM
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pam_err = pam_start("rsh", locuser, &pamc, &pamh);
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if (pam_err != PAM_SUCCESS) {
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syslog(LOG_ERR|LOG_AUTH, "pam_start(): %s",
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pam_strerror(pamh, pam_err));
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rshd_errx(EXIT_FAILURE, incorrect);
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}
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if ((pam_err = pam_set_item(pamh, PAM_RUSER, remuser)) != PAM_SUCCESS ||
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(pam_err = pam_set_item(pamh, PAM_RHOST, hostname)) != PAM_SUCCESS){
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syslog(LOG_ERR|LOG_AUTH, "pam_set_item(): %s",
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pam_strerror(pamh, pam_err));
|
|
rshd_errx(EXIT_FAILURE, incorrect);
|
|
}
|
|
|
|
pam_err = pam_authenticate(pamh, 0);
|
|
if (pam_err == PAM_SUCCESS) {
|
|
if ((pam_err = pam_get_user(pamh, &cp, NULL)) == PAM_SUCCESS) {
|
|
(void)strlcpy(locuser, cp, sizeof(locuser));
|
|
/* XXX truncation! */
|
|
}
|
|
pam_err = pam_acct_mgmt(pamh, 0);
|
|
}
|
|
if (pam_err != PAM_SUCCESS) {
|
|
errorstr = incorrect;
|
|
errormsg = pam_strerror(pamh, pam_err);
|
|
goto badlogin;
|
|
}
|
|
#endif /* USE_PAM */
|
|
setpwent();
|
|
if (getpwnam_r(locuser, &pwres, pwbuf, sizeof(pwbuf), &pwd) != 0 ||
|
|
pwd == NULL) {
|
|
syslog(LOG_INFO|LOG_AUTH,
|
|
"%s@%s as %s: unknown login. cmd='%.80s'",
|
|
remuser, hostname, locuser, cmdbuf);
|
|
if (errorstr == NULL)
|
|
errorstr = "Permission denied.";
|
|
rshd_errx(EXIT_FAILURE, errorstr, errorhost);
|
|
}
|
|
#ifdef LOGIN_CAP
|
|
lc = login_getclass(pwd ? pwd->pw_class : NULL);
|
|
#endif
|
|
|
|
if (chdir(pwd->pw_dir) < 0) {
|
|
if (chdir("/") < 0
|
|
#ifdef LOGIN_CAP
|
|
|| login_getcapbool(lc, "requirehome", pwd->pw_uid ? 1 : 0)
|
|
#endif
|
|
) {
|
|
syslog(LOG_INFO|LOG_AUTH,
|
|
"%s@%s as %s: no home directory. cmd='%.80s'",
|
|
remuser, hostname, locuser, cmdbuf);
|
|
rshd_errx(EXIT_SUCCESS, "No remote home directory.");
|
|
}
|
|
}
|
|
|
|
#ifndef USE_PAM
|
|
if (errorstr ||
|
|
(pwd->pw_passwd != 0 && *pwd->pw_passwd != '\0' &&
|
|
iruserok_sa(fromp, fromp->sa_len, pwd->pw_uid == 0, remuser,
|
|
locuser) < 0)) {
|
|
errormsg = __rcmd_errstr ? __rcmd_errstr : "unknown error";
|
|
if (errorstr == NULL)
|
|
errorstr = "Permission denied.";
|
|
goto badlogin;
|
|
}
|
|
|
|
if (pwd->pw_uid && !access(_PATH_NOLOGIN, F_OK))
|
|
rshd_errx(EXIT_FAILURE, "Logins currently disabled.");
|
|
#endif
|
|
|
|
#ifdef LOGIN_CAP
|
|
/*
|
|
* 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(EXIT_FAILURE);
|
|
}
|
|
#else
|
|
initgroups(pwd->pw_name, pwd->pw_gid);
|
|
#endif
|
|
|
|
#ifdef USE_PAM
|
|
if ((pam_err = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
|
|
syslog(LOG_ERR, "pam_open_session: %s",
|
|
pam_strerror(pamh, pam_err));
|
|
} else if ((pam_err = pam_setcred(pamh, PAM_ESTABLISH_CRED))
|
|
!= PAM_SUCCESS) {
|
|
syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, pam_err));
|
|
}
|
|
#endif
|
|
|
|
(void)write(STDERR_FILENO, "\0", 1);
|
|
sent_null = 1;
|
|
|
|
if (port) {
|
|
if (pipe(pv) < 0)
|
|
rshd_errx(EXIT_FAILURE, "Can't make pipe. (%s)",
|
|
strerror(errno));
|
|
pid = fork();
|
|
if (pid == -1)
|
|
rshd_errx(EXIT_FAILURE, "Can't fork. (%s)",
|
|
strerror(errno));
|
|
if (pid) {
|
|
(void)close(STDIN_FILENO);
|
|
(void)close(STDOUT_FILENO);
|
|
(void)close(STDERR_FILENO);
|
|
(void)close(pv[1]);
|
|
|
|
set[0].fd = s;
|
|
set[0].events = POLLIN;
|
|
set[1].fd = pv[0];
|
|
set[1].events = POLLIN;
|
|
ioctl(pv[0], FIONBIO, (char *)&one);
|
|
|
|
/* should set s nbio! */
|
|
do {
|
|
#ifdef __minix
|
|
if (set[0].events == 0 && set[1].events == 0)
|
|
break;
|
|
#endif /* __minix */
|
|
if (poll(set, 2, INFTIM) < 0)
|
|
break;
|
|
if (set[0].revents & POLLIN) {
|
|
int ret;
|
|
|
|
ret = read(s, &sig, 1);
|
|
if (ret <= 0)
|
|
set[0].events = 0;
|
|
else
|
|
killpg(pid, sig);
|
|
}
|
|
if (set[1].revents & POLLIN) {
|
|
errno = 0;
|
|
cc = read(pv[0], buf, sizeof(buf));
|
|
if (cc <= 0) {
|
|
shutdown(s, SHUT_RDWR);
|
|
set[1].events = 0;
|
|
} else {
|
|
(void)write(s, buf, cc);
|
|
}
|
|
}
|
|
|
|
} while ((set[0].revents | set[1].revents) & POLLIN);
|
|
PAM_END;
|
|
exit(EXIT_SUCCESS);
|
|
}
|
|
(void)close(s);
|
|
(void)close(pv[0]);
|
|
(void)dup2(pv[1], STDERR_FILENO);
|
|
close(pv[1]);
|
|
}
|
|
#ifdef USE_PAM
|
|
else {
|
|
pid = fork();
|
|
if (pid == -1)
|
|
rshd_errx(EXIT_FAILURE, "Can't fork. (%s)",
|
|
strerror(errno));
|
|
if (pid) {
|
|
pid_t xpid;
|
|
int status;
|
|
if ((xpid = waitpid(pid, &status, 0)) != pid) {
|
|
pam_err = pam_close_session(pamh, 0);
|
|
if (pam_err != PAM_SUCCESS) {
|
|
syslog(LOG_ERR,
|
|
"pam_close_session: %s",
|
|
pam_strerror(pamh, pam_err));
|
|
}
|
|
PAM_END;
|
|
if (xpid != -1)
|
|
syslog(LOG_WARNING,
|
|
"wrong PID: %d != %d", pid, xpid);
|
|
else
|
|
syslog(LOG_WARNING,
|
|
"wait pid=%d failed %m", pid);
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
exit(EXIT_SUCCESS);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#ifdef F_CLOSEM
|
|
(void)fcntl(STDERR_FILENO + 1, F_CLOSEM, 0);
|
|
#else
|
|
for (fd = getdtablesize(); fd > STDERR_FILENO; fd--)
|
|
(void)close(fd);
|
|
#endif
|
|
if (setsid() == -1)
|
|
syslog(LOG_ERR, "setsid() failed: %m");
|
|
#ifdef USE_PAM
|
|
if (setlogin(pwd->pw_name) < 0)
|
|
syslog(LOG_ERR, "setlogin() failed: %m");
|
|
|
|
if (*pwd->pw_shell == '\0')
|
|
pwd->pw_shell = __UNCONST(_PATH_BSHELL);
|
|
|
|
(void)pam_setenv(pamh, "HOME", pwd->pw_dir, 1);
|
|
(void)pam_setenv(pamh, "SHELL", pwd->pw_shell, 1);
|
|
(void)pam_setenv(pamh, "USER", pwd->pw_name, 1);
|
|
(void)pam_setenv(pamh, "PATH", _PATH_DEFPATH, 1);
|
|
environ = pam_getenvlist(pamh);
|
|
(void)pam_end(pamh, pam_err);
|
|
#else
|
|
#ifdef LOGIN_CAP
|
|
{
|
|
char *sh;
|
|
if ((sh = login_getcapstr(lc, "shell", NULL, NULL))) {
|
|
if(!(sh = strdup(sh))) {
|
|
syslog(LOG_ERR, "Cannot alloc mem");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
pwd->pw_shell = sh;
|
|
}
|
|
}
|
|
#endif
|
|
{
|
|
static char *envinit[] = { NULL };
|
|
environ = envinit;
|
|
}
|
|
setenv("PATH", _PATH_DEFPATH, 1);
|
|
setenv("HOME", pwd->pw_dir, 1);
|
|
setenv("SHELL", pwd->pw_shell, 1);
|
|
setenv("USER", pwd->pw_name, 1);
|
|
#endif
|
|
|
|
cp = strrchr(pwd->pw_shell, '/');
|
|
if (cp)
|
|
cp++;
|
|
else
|
|
cp = pwd->pw_shell;
|
|
|
|
#ifdef LOGIN_CAP
|
|
if (setusercontext(lc, pwd, pwd->pw_uid,
|
|
LOGIN_SETALL & ~LOGIN_SETGROUP) < 0) {
|
|
syslog(LOG_ERR, "setusercontext(): %m");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
login_close(lc);
|
|
#else
|
|
(void)setgid((gid_t)pwd->pw_gid);
|
|
(void)setuid((uid_t)pwd->pw_uid);
|
|
#endif
|
|
endpwent();
|
|
if (log_success || pwd->pw_uid == 0) {
|
|
syslog(LOG_INFO|LOG_AUTH, "%s@%s as %s: cmd='%.80s'",
|
|
remuser, hostname, locuser, cmdbuf);
|
|
}
|
|
(void)execl(pwd->pw_shell, cp, "-c", cmdbuf, NULL);
|
|
rshd_errx(EXIT_FAILURE, "%s: %s", pwd->pw_shell, strerror(errno));
|
|
badlogin:
|
|
syslog(LOG_INFO|LOG_AUTH,
|
|
"%s@%s as %s: permission denied (%s). cmd='%.80s'",
|
|
remuser, hostname, locuser, errormsg, cmdbuf);
|
|
rshd_errx(EXIT_FAILURE, errorstr, errorhost);
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
|
|
#include <stdarg.h>
|
|
|
|
static void
|
|
rshd_errx(int error, const char *fmt, ...)
|
|
{
|
|
va_list ap;
|
|
int len, rv;
|
|
char *bp, buf[BUFSIZ];
|
|
va_start(ap, fmt);
|
|
bp = buf;
|
|
if (sent_null == 0) {
|
|
*bp++ = 1;
|
|
len = 1;
|
|
} else
|
|
len = 0;
|
|
rv = vsnprintf(bp, sizeof(buf) - 2, fmt, ap);
|
|
bp[rv++] = '\n';
|
|
(void)write(STDERR_FILENO, buf, len + rv);
|
|
va_end(ap);
|
|
exit(error);
|
|
}
|
|
|
|
static void
|
|
getstr(char *buf, int cnt, const char *err)
|
|
{
|
|
char c;
|
|
|
|
do {
|
|
if (read(STDIN_FILENO, &c, 1) != 1)
|
|
exit(EXIT_FAILURE);
|
|
*buf++ = c;
|
|
if (--cnt == 0)
|
|
rshd_errx(EXIT_FAILURE, "%s too long", err);
|
|
} 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.
|
|
*/
|
|
static int
|
|
local_domain(char *h)
|
|
{
|
|
char localhost[MAXHOSTNAMELEN + 1];
|
|
char *p1, *p2;
|
|
|
|
localhost[0] = 0;
|
|
(void)gethostname(localhost, sizeof(localhost));
|
|
localhost[sizeof(localhost) - 1] = '\0';
|
|
p1 = topdomain(localhost);
|
|
p2 = topdomain(h);
|
|
if (p1 == NULL || p2 == NULL || !strcasecmp(p1, p2))
|
|
return (1);
|
|
return (0);
|
|
}
|
|
|
|
static 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);
|
|
}
|
|
|
|
static void
|
|
usage(void)
|
|
{
|
|
|
|
syslog(LOG_ERR, "Usage: %s [-%s]", getprogname(), OPTIONS);
|
|
exit(EXIT_FAILURE);
|
|
}
|