1039 lines
24 KiB
C
1039 lines
24 KiB
C
/* $NetBSD: rcmd.c,v 1.68 2012/07/14 15:06:26 darrenr Exp $ */
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/*
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* Copyright (c) 1983, 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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#if defined(LIBC_SCCS) && !defined(lint)
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#if 0
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static char sccsid[] = "@(#)rcmd.c 8.3 (Berkeley) 3/26/94";
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#else
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__RCSID("$NetBSD: rcmd.c,v 1.68 2012/07/14 15:06:26 darrenr Exp $");
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#endif
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#endif /* LIBC_SCCS and not lint */
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#ifdef _LIBC
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#include "namespace.h"
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#endif
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#include <sys/param.h>
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#include <sys/socket.h>
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#include <sys/stat.h>
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#include <sys/poll.h>
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#include <sys/wait.h>
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#include <netinet/in.h>
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#ifndef __minix
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#include <rpc/rpc.h>
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#endif
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#include <arpa/inet.h>
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#include <netgroup.h>
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#include <assert.h>
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#include <ctype.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 <grp.h>
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#include <netdb.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 "pathnames.h"
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int orcmd(char **, u_int, const char *, const char *, const char *, int *);
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int orcmd_af(char **, u_int, const char *, const char *, const char *,
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int *, int);
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int __ivaliduser(FILE *, u_int32_t, const char *, const char *);
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int __ivaliduser_sa(FILE *, const struct sockaddr *, socklen_t,
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const char *, const char *);
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static int rshrcmd(int, char **, u_int32_t, const char *,
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const char *, const char *, int *, const char *);
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static int resrcmd(struct addrinfo *, char **, u_int32_t, const char *,
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const char *, const char *, int *);
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static int __icheckhost(const struct sockaddr *, socklen_t,
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const char *);
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static char *__gethostloop(const struct sockaddr *, socklen_t);
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int
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rcmd(char **ahost, int rport, const char *locuser, const char *remuser,
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const char *cmd, int *fd2p)
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{
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return rcmd_af(ahost, rport, locuser, remuser, cmd, fd2p, AF_INET);
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}
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int
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rcmd_af(char **ahost, int rport, const char *locuser, const char *remuser,
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const char *cmd, int *fd2p, int af)
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{
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static char hbuf[MAXHOSTNAMELEN];
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char pbuf[NI_MAXSERV];
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struct addrinfo hints, *res;
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int error;
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struct servent *sp;
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_DIAGASSERT(ahost != NULL);
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_DIAGASSERT(locuser != NULL);
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_DIAGASSERT(remuser != NULL);
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_DIAGASSERT(cmd != NULL);
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/* fd2p may be NULL */
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snprintf(pbuf, sizeof(pbuf), "%u", ntohs(rport));
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memset(&hints, 0, sizeof(hints));
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hints.ai_family = af;
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hints.ai_socktype = SOCK_STREAM;
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hints.ai_flags = AI_CANONNAME;
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error = getaddrinfo(*ahost, pbuf, &hints, &res);
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if (error) {
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warnx("%s: %s", *ahost, gai_strerror(error)); /*XXX*/
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return -1;
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}
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if (res->ai_canonname) {
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/*
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* Canonicalise hostname.
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* XXX: Should we really do this?
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*/
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strlcpy(hbuf, res->ai_canonname, sizeof(hbuf));
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*ahost = hbuf;
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}
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/*
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* Check if rport is the same as the shell port, and that the fd2p. If
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* it is not, the program isn't expecting 'rsh' and so we can't use the
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* RCMD_CMD environment.
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*/
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sp = getservbyname("shell", "tcp");
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if (sp != NULL && sp->s_port == rport)
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error = rshrcmd(af, ahost, (u_int32_t)rport,
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locuser, remuser, cmd, fd2p, getenv("RCMD_CMD"));
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else
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error = resrcmd(res, ahost, (u_int32_t)rport,
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locuser, remuser, cmd, fd2p);
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freeaddrinfo(res);
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return error;
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}
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/* this is simply a wrapper around hprcmd() that handles ahost first */
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int
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orcmd(char **ahost, u_int rport, const char *locuser, const char *remuser,
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const char *cmd, int *fd2p)
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{
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return orcmd_af(ahost, rport, locuser, remuser, cmd, fd2p, AF_INET);
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}
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int
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orcmd_af(char **ahost, u_int rport, const char *locuser, const char *remuser,
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const char *cmd, int *fd2p, int af)
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{
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static char hbuf[MAXHOSTNAMELEN];
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char pbuf[NI_MAXSERV];
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struct addrinfo hints, *res;
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int error;
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_DIAGASSERT(ahost != NULL);
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_DIAGASSERT(locuser != NULL);
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_DIAGASSERT(remuser != NULL);
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_DIAGASSERT(cmd != NULL);
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/* fd2p may be NULL */
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snprintf(pbuf, sizeof(pbuf), "%u", ntohs(rport));
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memset(&hints, 0, sizeof(hints));
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hints.ai_family = af;
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hints.ai_socktype = SOCK_STREAM;
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hints.ai_flags = AI_CANONNAME;
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error = getaddrinfo(*ahost, pbuf, &hints, &res);
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if (error) {
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warnx("%s: %s", *ahost, gai_strerror(error)); /*XXX*/
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return -1;
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}
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if (res->ai_canonname) {
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strlcpy(hbuf, res->ai_canonname, sizeof(hbuf));
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*ahost = hbuf;
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}
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error = resrcmd(res, ahost, rport, locuser, remuser, cmd, fd2p);
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freeaddrinfo(res);
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return error;
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}
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/*ARGSUSED*/
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static int
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resrcmd(struct addrinfo *res, char **ahost, u_int32_t rport,
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const char *locuser, const char *remuser, const char *cmd, int *fd2p)
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{
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struct addrinfo *r;
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struct sockaddr_storage from;
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struct pollfd reads[2];
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#ifdef __minix
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/* No support for OOB data in Minix. */
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#else
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sigset_t nmask, omask;
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#endif /* !__minix */
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pid_t pid;
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int s, lport, timo;
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int pollr;
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char c;
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int refused;
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_DIAGASSERT(res != NULL);
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_DIAGASSERT(ahost != NULL);
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_DIAGASSERT(locuser != NULL);
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_DIAGASSERT(remuser != NULL);
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_DIAGASSERT(cmd != NULL);
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/* fd2p may be NULL */
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r = res;
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refused = 0;
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pid = getpid();
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#ifndef __minix
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/* Minix has no support for OOB data,
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no need to block SIGURG. */
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sigemptyset(&nmask);
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sigaddset(&nmask, SIGURG);
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if (sigprocmask(SIG_BLOCK, &nmask, &omask) == -1)
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return -1;
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#endif /* !__minix */
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for (timo = 1, lport = IPPORT_RESERVED - 1;;) {
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s = rresvport_af(&lport, r->ai_family);
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if (s < 0) {
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if (errno == EAGAIN)
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warnx("rcmd: socket: All ports in use");
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else
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warn("rcmd: socket");
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if (r->ai_next) {
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r = r->ai_next;
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continue;
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} else {
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#ifndef __minix
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(void)sigprocmask(SIG_SETMASK, &omask, NULL);
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#endif /* !__minix */
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return -1;
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}
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}
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#ifndef __minix
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/* No OOB support in Minix. */
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fcntl(s, F_SETOWN, pid);
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#endif /* !__minix */
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if (connect(s, r->ai_addr, r->ai_addrlen) >= 0)
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break;
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(void)close(s);
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if (errno == EADDRINUSE) {
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lport--;
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continue;
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} else if (errno == ECONNREFUSED)
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refused++;
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if (r->ai_next) {
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int oerrno = errno;
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char hbuf[NI_MAXHOST];
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const int niflags = NI_NUMERICHOST;
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hbuf[0] = '\0';
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if (getnameinfo(r->ai_addr, r->ai_addrlen,
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hbuf, (socklen_t)sizeof(hbuf), NULL, 0, niflags) !=
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0)
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strlcpy(hbuf, "(invalid)", sizeof(hbuf));
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errno = oerrno;
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warn("rcmd: connect to address %s", hbuf);
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r = r->ai_next;
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hbuf[0] = '\0';
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if (getnameinfo(r->ai_addr, r->ai_addrlen,
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hbuf, (socklen_t)sizeof(hbuf), NULL, 0, niflags) !=
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0)
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strlcpy(hbuf, "(invalid)", sizeof(hbuf));
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(void)fprintf(stderr, "Trying %s...\n", hbuf);
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continue;
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}
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if (refused && timo <= 16) {
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(void)sleep((unsigned int)timo);
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timo *= 2;
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r = res;
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refused = 0;
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continue;
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}
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(void)fprintf(stderr, "%s: %s\n", res->ai_canonname,
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strerror(errno));
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#ifndef __minix
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/* No OOB support in Minix. */
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(void)sigprocmask(SIG_SETMASK, &omask, NULL);
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#endif /* !__minix */
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return -1;
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}
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lport--;
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if (fd2p == 0) {
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write(s, "", 1);
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lport = 0;
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} else {
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char num[8];
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int s2 = rresvport_af(&lport, r->ai_family), s3;
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socklen_t len = sizeof(from);
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if (s2 < 0)
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goto bad;
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listen(s2, 1);
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(void)snprintf(num, sizeof(num), "%d", lport);
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if (write(s, num, strlen(num) + 1) !=
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(ssize_t) (strlen(num) + 1)) {
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warn("rcmd: write (setting up stderr)");
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(void)close(s2);
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goto bad;
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}
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reads[0].fd = s;
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reads[0].events = POLLIN;
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reads[1].fd = s2;
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reads[1].events = POLLIN;
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errno = 0;
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pollr = poll(reads, 2, INFTIM);
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if (pollr < 1 || (reads[1].revents & POLLIN) == 0) {
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if (errno != 0)
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warn("poll: setting up stderr");
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else
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warnx(
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"poll: protocol failure in circuit setup");
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(void)close(s2);
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goto bad;
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}
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s3 = accept(s2, (struct sockaddr *)(void *)&from, &len);
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(void)close(s2);
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if (s3 < 0) {
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warn("rcmd: accept");
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lport = 0;
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goto bad;
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}
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*fd2p = s3;
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switch (((struct sockaddr *)(void *)&from)->sa_family) {
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case AF_INET:
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#ifdef INET6
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case AF_INET6:
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#endif
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if (getnameinfo((struct sockaddr *)(void *)&from, len,
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NULL, 0, num, (socklen_t)sizeof(num),
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NI_NUMERICSERV) != 0 ||
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(atoi(num) >= IPPORT_RESERVED ||
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atoi(num) < IPPORT_RESERVED / 2)) {
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warnx(
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"rcmd: protocol failure in circuit setup.");
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goto bad2;
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}
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break;
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default:
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break;
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}
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}
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(void)write(s, locuser, strlen(locuser)+1);
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(void)write(s, remuser, strlen(remuser)+1);
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(void)write(s, cmd, strlen(cmd)+1);
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if (read(s, &c, 1) != 1) {
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warn("%s", *ahost);
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goto bad2;
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}
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if (c != 0) {
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while (read(s, &c, 1) == 1) {
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(void)write(STDERR_FILENO, &c, 1);
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if (c == '\n')
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break;
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}
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goto bad2;
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}
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#ifndef __minix
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(void)sigprocmask(SIG_SETMASK, &omask, NULL);
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#endif /* __minix */
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return s;
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bad2:
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if (lport)
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(void)close(*fd2p);
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bad:
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(void)close(s);
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#ifndef __minix
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(void)sigprocmask(SIG_SETMASK, &omask, NULL);
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#endif /* __minix */
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return -1;
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}
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/*
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* based on code written by Chris Siebenmann <cks@utcc.utoronto.ca>
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*/
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/* ARGSUSED */
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static int
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rshrcmd(int af, char **ahost, u_int32_t rport, const char *locuser,
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const char *remuser, const char *cmd, int *fd2p, const char *rshcmd)
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{
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pid_t pid;
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int sp[2], ep[2];
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char *p;
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struct passwd *pw, pwres;
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char pwbuf[1024];
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_DIAGASSERT(ahost != NULL);
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_DIAGASSERT(locuser != NULL);
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_DIAGASSERT(remuser != NULL);
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_DIAGASSERT(cmd != NULL);
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/* fd2p may be NULL */
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/* What rsh/shell to use. */
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if (rshcmd == NULL)
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rshcmd = _PATH_BIN_RCMD;
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/* locuser must exist on this host. */
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if (getpwnam_r(locuser, &pwres, pwbuf, sizeof(pwbuf), &pw) != 0 ||
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pw == NULL) {
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warnx("%s: unknown user: %s", __func__, locuser);
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return -1;
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}
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/* get a socketpair we'll use for stdin and stdout. */
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if (socketpair(AF_LOCAL, SOCK_STREAM, 0, sp) < 0) {
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warn("%s: socketpair", __func__);
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return -1;
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}
|
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/* we will use this for the fd2 pointer */
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if (fd2p) {
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if (socketpair(AF_LOCAL, SOCK_STREAM, 0, ep) < 0) {
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warn("%s: socketpair", __func__);
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return -1;
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}
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*fd2p = ep[0];
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}
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|
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pid = fork();
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if (pid < 0) {
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warn("%s: fork", __func__);
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return -1;
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}
|
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if (pid == 0) {
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/*
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* child
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* - we use sp[1] to be stdin/stdout, and close sp[0]
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* - with fd2p, we use ep[1] for stderr, and close ep[0]
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*/
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(void)close(sp[0]);
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if (dup2(sp[1], 0) < 0 || dup2(0, 1) < 0) {
|
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warn("%s: dup2", __func__);
|
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_exit(1);
|
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}
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(void)close(sp[1]);
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if (fd2p) {
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if (dup2(ep[1], 2) < 0) {
|
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warn("%s: dup2", __func__);
|
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_exit(1);
|
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}
|
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(void)close(ep[0]);
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(void)close(ep[1]);
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} else if (dup2(0, 2) < 0) {
|
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warn("%s: dup2", __func__);
|
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_exit(1);
|
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}
|
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/* fork again to lose parent. */
|
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pid = fork();
|
|
if (pid < 0) {
|
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warn("%s: second fork", __func__);
|
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_exit(1);
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}
|
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if (pid > 0)
|
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_exit(0);
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/* Orphan. Become local user for rshprog. */
|
|
if (setuid(pw->pw_uid)) {
|
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warn("%s: setuid(%lu)", __func__, (u_long)pw->pw_uid);
|
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_exit(1);
|
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}
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|
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/*
|
|
* If we are rcmd'ing to "localhost" as the same user as we
|
|
* are, then avoid running remote shell for efficiency.
|
|
*/
|
|
if (strcmp(*ahost, "localhost") == 0 &&
|
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strcmp(locuser, remuser) == 0) {
|
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if (pw->pw_shell[0] == '\0')
|
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rshcmd = _PATH_BSHELL;
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else
|
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rshcmd = pw->pw_shell;
|
|
p = strrchr(rshcmd, '/');
|
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execlp(rshcmd, p ? p + 1 : rshcmd, "-c", cmd, NULL);
|
|
} else {
|
|
const char *program;
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program = strrchr(rshcmd, '/');
|
|
program = program ? program + 1 : rshcmd;
|
|
switch (af) {
|
|
case AF_INET:
|
|
execlp(rshcmd, program, "-4", "-l", remuser,
|
|
*ahost, cmd, NULL);
|
|
break;
|
|
|
|
case AF_INET6:
|
|
execlp(rshcmd, program, "-6", "-l", remuser,
|
|
*ahost, cmd, NULL);
|
|
break;
|
|
|
|
default:
|
|
/* typically AF_UNSPEC, plus whatever */
|
|
execlp(rshcmd, program, "-l", remuser,
|
|
*ahost, cmd, NULL);
|
|
break;
|
|
}
|
|
}
|
|
warn("%s: exec %s", __func__, rshcmd);
|
|
_exit(1);
|
|
}
|
|
/* Parent */
|
|
(void)close(sp[1]);
|
|
if (fd2p)
|
|
(void)close(ep[1]);
|
|
|
|
(void)waitpid(pid, NULL, 0);
|
|
return sp[0];
|
|
}
|
|
|
|
int
|
|
rresvport(int *alport)
|
|
{
|
|
|
|
_DIAGASSERT(alport != NULL);
|
|
|
|
return rresvport_af(alport, AF_INET);
|
|
}
|
|
|
|
int
|
|
rresvport_af(int *alport, int family)
|
|
{
|
|
return rresvport_af_addr(alport, family, NULL);
|
|
}
|
|
|
|
int
|
|
rresvport_af_addr(int *alport, int family, void *addr)
|
|
{
|
|
struct sockaddr_storage ss;
|
|
struct sockaddr *sa;
|
|
socklen_t salen;
|
|
int s;
|
|
u_int16_t *portp;
|
|
|
|
_DIAGASSERT(alport != NULL);
|
|
|
|
memset(&ss, 0, sizeof(ss));
|
|
sa = (struct sockaddr *)(void *)&ss;
|
|
switch (family) {
|
|
case AF_INET:
|
|
#ifdef BSD4_4
|
|
sa->sa_len =
|
|
#endif
|
|
salen = sizeof(struct sockaddr_in);
|
|
if (addr)
|
|
((struct sockaddr_in *)(void *)sa)->sin_addr =
|
|
((struct sockaddr_in *)addr)->sin_addr;
|
|
portp = &((struct sockaddr_in *)(void *)sa)->sin_port;
|
|
break;
|
|
#ifdef INET6
|
|
case AF_INET6:
|
|
#ifdef BSD4_4
|
|
sa->sa_len =
|
|
#endif
|
|
salen = sizeof(struct sockaddr_in6);
|
|
if (addr)
|
|
((struct sockaddr_in6 *)(void *)sa)->sin6_addr =
|
|
((struct sockaddr_in6 *)addr)->sin6_addr;
|
|
portp = &((struct sockaddr_in6 *)(void *)sa)->sin6_port;
|
|
break;
|
|
#endif
|
|
default:
|
|
errno = EAFNOSUPPORT;
|
|
return -1;
|
|
}
|
|
sa->sa_family = family;
|
|
s = socket(family, SOCK_STREAM, 0);
|
|
if (s < 0)
|
|
return -1;
|
|
#if defined(BSD4_4) && !defined(__minix)
|
|
switch (family) {
|
|
case AF_INET:
|
|
case AF_INET6:
|
|
*portp = 0;
|
|
if (bindresvport(s, (struct sockaddr_in *)(void *)sa) < 0) {
|
|
int sverr = errno;
|
|
|
|
(void)close(s);
|
|
errno = sverr;
|
|
return -1;
|
|
}
|
|
*alport = (int)ntohs(*portp);
|
|
return s;
|
|
default:
|
|
/* is it necessary to try keep code for other AFs? */
|
|
break;
|
|
}
|
|
#endif
|
|
for (;;) {
|
|
*portp = htons((u_short)*alport);
|
|
if (bind(s, sa, salen) >= 0)
|
|
return s;
|
|
if (errno != EADDRINUSE) {
|
|
(void)close(s);
|
|
return -1;
|
|
}
|
|
(*alport)--;
|
|
if (*alport == IPPORT_RESERVED/2) {
|
|
(void)close(s);
|
|
errno = EAGAIN; /* close */
|
|
return -1;
|
|
}
|
|
}
|
|
}
|
|
|
|
int __check_rhosts_file = 1;
|
|
const char *__rcmd_errstr;
|
|
|
|
int
|
|
ruserok(const char *rhost, int superuser, const char *ruser, const char *luser)
|
|
{
|
|
struct addrinfo hints, *res, *r;
|
|
int error;
|
|
|
|
_DIAGASSERT(rhost != NULL);
|
|
_DIAGASSERT(ruser != NULL);
|
|
_DIAGASSERT(luser != NULL);
|
|
|
|
memset(&hints, 0, sizeof(hints));
|
|
hints.ai_family = PF_UNSPEC;
|
|
hints.ai_socktype = SOCK_DGRAM; /*dummy*/
|
|
error = getaddrinfo(rhost, "0", &hints, &res);
|
|
if (error)
|
|
return -1;
|
|
|
|
for (r = res; r; r = r->ai_next) {
|
|
if (iruserok_sa(r->ai_addr, (int)r->ai_addrlen, superuser,
|
|
ruser, luser) == 0) {
|
|
freeaddrinfo(res);
|
|
return 0;
|
|
}
|
|
}
|
|
freeaddrinfo(res);
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* New .rhosts strategy: We are passed an ip address. We spin through
|
|
* hosts.equiv and .rhosts looking for a match. When the .rhosts only
|
|
* has ip addresses, we don't have to trust a nameserver. When it
|
|
* contains hostnames, we spin through the list of addresses the nameserver
|
|
* gives us and look for a match.
|
|
*
|
|
* Returns 0 if ok, -1 if not ok.
|
|
*/
|
|
int
|
|
iruserok(u_int32_t raddr, int superuser, const char *ruser, const char *luser)
|
|
{
|
|
struct sockaddr_in irsin;
|
|
|
|
memset(&irsin, 0, sizeof(irsin));
|
|
irsin.sin_family = AF_INET;
|
|
#ifdef BSD4_4
|
|
irsin.sin_len = sizeof(irsin);
|
|
#endif
|
|
memcpy(&irsin.sin_addr, &raddr, sizeof(irsin.sin_addr));
|
|
return iruserok_sa(&irsin, (socklen_t)sizeof(irsin), superuser, ruser,
|
|
luser);
|
|
}
|
|
|
|
/*
|
|
* 2nd and 3rd arguments are typed like this, to avoid dependency between
|
|
* unistd.h and sys/socket.h. There's no better way.
|
|
*/
|
|
int
|
|
iruserok_sa(const void *raddr, int rlen, int superuser, const char *ruser,
|
|
const char *luser)
|
|
{
|
|
const struct sockaddr *sa;
|
|
struct stat sbuf;
|
|
struct passwd *pwd, pwres;
|
|
FILE *hostf;
|
|
uid_t uid;
|
|
gid_t gid;
|
|
int isvaliduser;
|
|
char pbuf[MAXPATHLEN];
|
|
char pwbuf[1024];
|
|
|
|
_DIAGASSERT(raddr != NULL);
|
|
_DIAGASSERT(ruser != NULL);
|
|
_DIAGASSERT(luser != NULL);
|
|
|
|
sa = raddr;
|
|
|
|
__rcmd_errstr = NULL;
|
|
|
|
hostf = superuser ? NULL : fopen(_PATH_HEQUIV, "r");
|
|
|
|
if (hostf) {
|
|
if (__ivaliduser_sa(hostf, sa, (socklen_t)rlen, luser,
|
|
ruser) == 0) {
|
|
(void)fclose(hostf);
|
|
return 0;
|
|
}
|
|
(void)fclose(hostf);
|
|
}
|
|
|
|
isvaliduser = -1;
|
|
if (__check_rhosts_file || superuser) {
|
|
|
|
if (getpwnam_r(luser, &pwres, pwbuf, sizeof(pwbuf), &pwd) != 0
|
|
|| pwd == NULL)
|
|
return -1;
|
|
(void)strlcpy(pbuf, pwd->pw_dir, sizeof(pbuf));
|
|
(void)strlcat(pbuf, "/.rhosts", sizeof(pbuf));
|
|
|
|
/*
|
|
* Change effective uid while opening and reading .rhosts.
|
|
* If root and reading an NFS mounted file system, can't
|
|
* read files that are protected read/write owner only.
|
|
*/
|
|
uid = geteuid();
|
|
gid = getegid();
|
|
(void)setegid(pwd->pw_gid);
|
|
initgroups(pwd->pw_name, pwd->pw_gid);
|
|
(void)seteuid(pwd->pw_uid);
|
|
hostf = fopen(pbuf, "r");
|
|
|
|
if (hostf != NULL) {
|
|
/*
|
|
* If not a regular file, or is owned by someone other
|
|
* than user or root or if writable by anyone but the
|
|
* owner, quit.
|
|
*/
|
|
if (lstat(pbuf, &sbuf) < 0)
|
|
__rcmd_errstr = ".rhosts lstat failed";
|
|
else if (!S_ISREG(sbuf.st_mode))
|
|
__rcmd_errstr = ".rhosts not regular file";
|
|
else if (fstat(fileno(hostf), &sbuf) < 0)
|
|
__rcmd_errstr = ".rhosts fstat failed";
|
|
else if (sbuf.st_uid && sbuf.st_uid != pwd->pw_uid)
|
|
__rcmd_errstr = "bad .rhosts owner";
|
|
else if (sbuf.st_mode & (S_IWGRP|S_IWOTH))
|
|
__rcmd_errstr =
|
|
".rhosts writable by other than owner";
|
|
else
|
|
isvaliduser =
|
|
__ivaliduser_sa(hostf, sa, (socklen_t)rlen,
|
|
luser, ruser);
|
|
|
|
(void)fclose(hostf);
|
|
}
|
|
(void)seteuid(uid);
|
|
(void)setegid(gid);
|
|
|
|
}
|
|
return isvaliduser;
|
|
}
|
|
|
|
/*
|
|
* XXX
|
|
* Don't make static, used by lpd(8). We will be able to change the function
|
|
* into static function, when we bump libc major #.
|
|
*
|
|
* Returns 0 if ok, -1 if not ok.
|
|
*/
|
|
#ifdef notdef /*_LIBC*/
|
|
static
|
|
#endif
|
|
int
|
|
__ivaliduser(FILE *hostf, u_int32_t raddr, const char *luser,
|
|
const char *ruser)
|
|
{
|
|
struct sockaddr_in ivusin;
|
|
|
|
memset(&ivusin, 0, sizeof(ivusin));
|
|
ivusin.sin_family = AF_INET;
|
|
#ifdef BSD4_4
|
|
ivusin.sin_len = sizeof(ivusin);
|
|
#endif
|
|
memcpy(&ivusin.sin_addr, &raddr, sizeof(ivusin.sin_addr));
|
|
return __ivaliduser_sa(hostf, (struct sockaddr *)(void *)&ivusin,
|
|
(socklen_t)sizeof(ivusin), luser, ruser);
|
|
}
|
|
|
|
#ifdef notdef /*_LIBC*/
|
|
static
|
|
#endif
|
|
int
|
|
__ivaliduser_sa(FILE *hostf, const struct sockaddr *raddr, socklen_t salen,
|
|
const char *luser, const char *ruser)
|
|
{
|
|
char *user, *p;
|
|
int ch;
|
|
char buf[MAXHOSTNAMELEN + 128]; /* host + login */
|
|
const char *auser, *ahost;
|
|
int hostok, userok;
|
|
char *rhost = NULL;
|
|
int firsttime = 1;
|
|
char domain[MAXHOSTNAMELEN];
|
|
|
|
getdomainname(domain, sizeof(domain));
|
|
|
|
_DIAGASSERT(hostf != NULL);
|
|
_DIAGASSERT(luser != NULL);
|
|
_DIAGASSERT(ruser != NULL);
|
|
|
|
while (fgets(buf, (int)sizeof(buf), hostf)) {
|
|
p = buf;
|
|
/* Skip lines that are too long. */
|
|
if (strchr(p, '\n') == NULL) {
|
|
while ((ch = getc(hostf)) != '\n' && ch != EOF)
|
|
;
|
|
continue;
|
|
}
|
|
while (*p != '\n' && *p != ' ' && *p != '\t' && *p != '\0') {
|
|
*p = isupper((unsigned char)*p) ?
|
|
tolower((unsigned char)*p) : *p;
|
|
p++;
|
|
}
|
|
if (*p == ' ' || *p == '\t') {
|
|
*p++ = '\0';
|
|
while (*p == ' ' || *p == '\t')
|
|
p++;
|
|
user = p;
|
|
while (*p != '\n' && *p != ' ' &&
|
|
*p != '\t' && *p != '\0')
|
|
p++;
|
|
} else
|
|
user = p;
|
|
*p = '\0';
|
|
|
|
if (p == buf)
|
|
continue;
|
|
|
|
auser = *user ? user : luser;
|
|
ahost = buf;
|
|
|
|
if (ahost[0] == '+')
|
|
switch (ahost[1]) {
|
|
case '\0':
|
|
hostok = 1;
|
|
break;
|
|
|
|
case '@':
|
|
if (firsttime) {
|
|
rhost = __gethostloop(raddr, salen);
|
|
firsttime = 0;
|
|
}
|
|
if (rhost)
|
|
hostok = innetgr(&ahost[2], rhost,
|
|
NULL, domain);
|
|
else
|
|
hostok = 0;
|
|
break;
|
|
|
|
default:
|
|
hostok = __icheckhost(raddr, salen, &ahost[1]);
|
|
break;
|
|
}
|
|
else if (ahost[0] == '-')
|
|
switch (ahost[1]) {
|
|
case '\0':
|
|
hostok = -1;
|
|
break;
|
|
|
|
case '@':
|
|
if (firsttime) {
|
|
rhost = __gethostloop(raddr, salen);
|
|
firsttime = 0;
|
|
}
|
|
if (rhost)
|
|
hostok = -innetgr(&ahost[2], rhost,
|
|
NULL, domain);
|
|
else
|
|
hostok = 0;
|
|
break;
|
|
|
|
default:
|
|
hostok =
|
|
-__icheckhost(raddr, salen, &ahost[1]);
|
|
break;
|
|
}
|
|
else
|
|
hostok = __icheckhost(raddr, salen, ahost);
|
|
|
|
|
|
if (auser[0] == '+')
|
|
switch (auser[1]) {
|
|
case '\0':
|
|
userok = 1;
|
|
break;
|
|
|
|
case '@':
|
|
userok = innetgr(&auser[2], NULL, ruser,
|
|
domain);
|
|
break;
|
|
|
|
default:
|
|
userok = strcmp(ruser, &auser[1]) == 0;
|
|
break;
|
|
}
|
|
else if (auser[0] == '-')
|
|
switch (auser[1]) {
|
|
case '\0':
|
|
userok = -1;
|
|
break;
|
|
|
|
case '@':
|
|
userok = -innetgr(&auser[2], NULL, ruser,
|
|
domain);
|
|
break;
|
|
|
|
default:
|
|
userok =
|
|
-(strcmp(ruser, &auser[1]) == 0 ? 1 : 0);
|
|
break;
|
|
}
|
|
else
|
|
userok = strcmp(ruser, auser) == 0;
|
|
|
|
/* Check if one component did not match */
|
|
if (hostok == 0 || userok == 0)
|
|
continue;
|
|
|
|
/* Check if we got a forbidden pair */
|
|
if (userok == -1 || hostok == -1)
|
|
return -1;
|
|
|
|
/* Check if we got a valid pair */
|
|
if (hostok == 1 && userok == 1)
|
|
return 0;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Returns "true" if match, 0 if no match.
|
|
*/
|
|
static int
|
|
__icheckhost(const struct sockaddr *raddr, socklen_t salen, const char *lhost)
|
|
{
|
|
struct addrinfo hints, *res, *r;
|
|
char h1[NI_MAXHOST], h2[NI_MAXHOST];
|
|
int error;
|
|
const int niflags = NI_NUMERICHOST;
|
|
|
|
_DIAGASSERT(raddr != NULL);
|
|
_DIAGASSERT(lhost != NULL);
|
|
|
|
h1[0] = '\0';
|
|
if (getnameinfo(raddr, salen, h1, (socklen_t)sizeof(h1), NULL, 0,
|
|
niflags) != 0)
|
|
return 0;
|
|
|
|
/* Resolve laddr into sockaddr */
|
|
memset(&hints, 0, sizeof(hints));
|
|
hints.ai_family = raddr->sa_family;
|
|
hints.ai_socktype = SOCK_DGRAM; /*dummy*/
|
|
res = NULL;
|
|
error = getaddrinfo(lhost, "0", &hints, &res);
|
|
if (error)
|
|
return 0;
|
|
|
|
/*
|
|
* Try string comparisons between raddr and laddr.
|
|
*/
|
|
for (r = res; r; r = r->ai_next) {
|
|
h2[0] = '\0';
|
|
if (getnameinfo(r->ai_addr, r->ai_addrlen, h2,
|
|
(socklen_t)sizeof(h2), NULL, 0, niflags) != 0)
|
|
continue;
|
|
if (strcmp(h1, h2) == 0) {
|
|
freeaddrinfo(res);
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
/* No match. */
|
|
freeaddrinfo(res);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Return the hostname associated with the supplied address.
|
|
* Do a reverse lookup as well for security. If a loop cannot
|
|
* be found, pack the numeric IP address into the string.
|
|
*/
|
|
static char *
|
|
__gethostloop(const struct sockaddr *raddr, socklen_t salen)
|
|
{
|
|
static char remotehost[NI_MAXHOST];
|
|
char h1[NI_MAXHOST], h2[NI_MAXHOST];
|
|
struct addrinfo hints, *res, *r;
|
|
int error;
|
|
const int niflags = NI_NUMERICHOST;
|
|
|
|
_DIAGASSERT(raddr != NULL);
|
|
|
|
h1[0] = remotehost[0] = '\0';
|
|
if (getnameinfo(raddr, salen, remotehost, (socklen_t)sizeof(remotehost),
|
|
NULL, 0, NI_NAMEREQD) != 0)
|
|
return NULL;
|
|
if (getnameinfo(raddr, salen, h1, (socklen_t)sizeof(h1), NULL, 0,
|
|
niflags) != 0)
|
|
return NULL;
|
|
|
|
/*
|
|
* Look up the name and check that the supplied
|
|
* address is in the list
|
|
*/
|
|
memset(&hints, 0, sizeof(hints));
|
|
hints.ai_family = raddr->sa_family;
|
|
hints.ai_socktype = SOCK_DGRAM; /*dummy*/
|
|
hints.ai_flags = AI_CANONNAME;
|
|
res = NULL;
|
|
error = getaddrinfo(remotehost, "0", &hints, &res);
|
|
if (error)
|
|
return NULL;
|
|
|
|
for (r = res; r; r = r->ai_next) {
|
|
h2[0] = '\0';
|
|
if (getnameinfo(r->ai_addr, r->ai_addrlen, h2,
|
|
(socklen_t)sizeof(h2), NULL, 0, niflags) != 0)
|
|
continue;
|
|
if (strcmp(h1, h2) == 0) {
|
|
freeaddrinfo(res);
|
|
return remotehost;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* either the DNS adminstrator has made a configuration
|
|
* mistake, or someone has attempted to spoof us
|
|
*/
|
|
syslog(LOG_NOTICE, "rcmd: address %s not listed for host %s",
|
|
h1, res->ai_canonname ? res->ai_canonname : remotehost);
|
|
freeaddrinfo(res);
|
|
return NULL;
|
|
}
|