2 * Copyright (c) 1983, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * $FreeBSD: src/lib/libc/net/rcmd.c,v 1.23.2.7 2002/08/26 16:17:49 jdp Exp $
36 #if defined(LIBC_SCCS) && !defined(lint)
37 static char sccsid[] = "@(#)rcmd.c 8.3 (Berkeley) 3/26/94";
38 #endif /* LIBC_SCCS and not lint */
40 #include <sys/param.h>
41 #include <sys/socket.h>
44 #include <netinet/in.h>
45 #include <arpa/inet.h>
59 #include <rpcsvc/yp_prot.h>
60 #include <rpcsvc/ypclnt.h>
62 #include <arpa/nameser.h>
64 /* wrapper for KAME-special getnameinfo() */
65 #ifndef NI_WITHSCOPEID
66 #define NI_WITHSCOPEID 0
69 extern int innetgr __P(( const char *, const char *, const char *, const char * ));
71 #define max(a, b) ((a > b) ? a : b)
73 int __ivaliduser __P((FILE *, u_int32_t, const char *, const char *));
74 int __ivaliduser_af __P((FILE *,const void *, const char *, const char *,
76 int __ivaliduser_sa __P((FILE *, const struct sockaddr *, socklen_t,
77 const char *,const char *));
78 static int __icheckhost __P((const struct sockaddr *, socklen_t,
81 char paddr[NI_MAXHOST];
84 rcmd(ahost, rport, locuser, remuser, cmd, fd2p)
87 const char *locuser, *remuser, *cmd;
90 return rcmd_af(ahost, rport, locuser, remuser, cmd, fd2p, AF_INET);
94 rcmd_af(ahost, rport, locuser, remuser, cmd, fd2p, af)
97 const char *locuser, *remuser, *cmd;
101 struct addrinfo hints, *res, *ai;
102 struct sockaddr_storage from;
106 int s, aport, lport, timo, error;
110 static char canonnamebuf[MAXDNAME]; /* is it proper here? */
112 /* call rcmdsh() with specified remote shell if appropriate. */
113 if (!issetugid() && (p = getenv("RSH"))) {
114 struct servent *sp = getservbyname("shell", "tcp");
116 if (sp && sp->s_port == rport)
117 return (rcmdsh(ahost, rport, locuser, remuser,
121 /* use rsh(1) if non-root and remote port is shell. */
123 struct servent *sp = getservbyname("shell", "tcp");
125 if (sp && sp->s_port == rport)
126 return (rcmdsh(ahost, rport, locuser, remuser,
132 memset(&hints, 0, sizeof(hints));
133 hints.ai_flags = AI_CANONNAME;
134 hints.ai_family = af;
135 hints.ai_socktype = SOCK_STREAM;
136 hints.ai_protocol = 0;
137 (void)snprintf(num, sizeof(num), "%d", ntohs(rport));
138 error = getaddrinfo(*ahost, num, &hints, &res);
140 fprintf(stderr, "rcmd: getaddrinfo: %s\n",
141 gai_strerror(error));
142 if (error == EAI_SYSTEM)
143 fprintf(stderr, "rcmd: getaddrinfo: %s\n",
148 if (res->ai_canonname
149 && strlen(res->ai_canonname) + 1 < sizeof(canonnamebuf)) {
150 strncpy(canonnamebuf, res->ai_canonname, sizeof(canonnamebuf));
151 *ahost = canonnamebuf;
154 for (ai = res; ai; ai = ai->ai_next)
158 oldmask = sigblock(sigmask(SIGURG));
159 for (timo = 1, lport = IPPORT_RESERVED - 1;;) {
160 s = rresvport_af(&lport, ai->ai_family);
162 if (errno != EAGAIN && ai->ai_next) {
167 (void)fprintf(stderr,
168 "rcmd: socket: All ports in use\n");
170 (void)fprintf(stderr, "rcmd: socket: %s\n",
176 _fcntl(s, F_SETOWN, pid);
177 if (connect(s, ai->ai_addr, ai->ai_addrlen) >= 0)
180 if (errno == EADDRINUSE) {
184 if (errno == ECONNREFUSED)
186 if (ai->ai_next == NULL && (!refused || timo > 16)) {
187 (void)fprintf(stderr, "%s: %s\n",
188 *ahost, strerror(errno));
196 getnameinfo(ai->ai_addr, ai->ai_addrlen,
197 paddr, sizeof(paddr),
199 NI_NUMERICHOST|NI_WITHSCOPEID);
200 (void)fprintf(stderr, "connect to address %s: ",
205 if ((ai = ai->ai_next) == NULL) {
206 /* refused && timo <= 16 */
207 struct timespec time_to_sleep, time_remaining;
209 time_to_sleep.tv_sec = timo;
210 time_to_sleep.tv_nsec = 0;
211 (void)_nanosleep(&time_to_sleep, &time_remaining);
217 getnameinfo(ai->ai_addr, ai->ai_addrlen,
218 paddr, sizeof(paddr),
220 NI_NUMERICHOST|NI_WITHSCOPEID);
221 fprintf(stderr, "Trying %s...\n", paddr);
230 int s2 = rresvport_af(&lport, ai->ai_family), s3;
231 int len = ai->ai_addrlen;
237 (void)snprintf(num, sizeof(num), "%d", lport);
238 if (_write(s, num, strlen(num)+1) != strlen(num)+1) {
239 (void)fprintf(stderr,
240 "rcmd: write (setting up stderr): %s\n",
246 if(nfds > FD_SETSIZE) {
247 fprintf(stderr, "rcmd: too many files\n");
256 if (select(nfds, &reads, 0, 0, 0) < 1 || !FD_ISSET(s2, &reads)){
258 (void)fprintf(stderr,
259 "rcmd: select (setting up stderr): %s\n",
262 (void)fprintf(stderr,
263 "select: protocol failure in circuit setup\n");
267 s3 = accept(s2, (struct sockaddr *)&from, &len);
268 switch (from.ss_family) {
270 aport = ntohs(((struct sockaddr_in *)&from)->sin_port);
274 aport = ntohs(((struct sockaddr_in6 *)&from)->sin6_port);
278 aport = 0; /* error */
282 * XXX careful for ftp bounce attacks. If discovered, shut them
283 * down and check for the real auxiliary channel to connect.
291 (void)fprintf(stderr,
292 "rcmd: accept: %s\n", strerror(errno));
297 if (aport >= IPPORT_RESERVED || aport < IPPORT_RESERVED / 2) {
298 (void)fprintf(stderr,
299 "socket: protocol failure in circuit setup.\n");
303 (void)_write(s, locuser, strlen(locuser)+1);
304 (void)_write(s, remuser, strlen(remuser)+1);
305 (void)_write(s, cmd, strlen(cmd)+1);
306 if (_read(s, &c, 1) != 1) {
307 (void)fprintf(stderr,
308 "rcmd: %s: %s\n", *ahost, strerror(errno));
312 while (_read(s, &c, 1) == 1) {
313 (void)_write(STDERR_FILENO, &c, 1);
336 return rresvport_af(port, AF_INET);
340 rresvport_af(alport, family)
344 struct sockaddr_storage ss;
347 memset(&ss, 0, sizeof(ss));
348 ss.ss_family = family;
351 ((struct sockaddr *)&ss)->sa_len = sizeof(struct sockaddr_in);
352 sport = &((struct sockaddr_in *)&ss)->sin_port;
353 ((struct sockaddr_in *)&ss)->sin_addr.s_addr = INADDR_ANY;
357 ((struct sockaddr *)&ss)->sa_len = sizeof(struct sockaddr_in6);
358 sport = &((struct sockaddr_in6 *)&ss)->sin6_port;
359 ((struct sockaddr_in6 *)&ss)->sin6_addr = in6addr_any;
363 errno = EAFNOSUPPORT;
367 s = socket(ss.ss_family, SOCK_STREAM, 0);
370 #if 0 /* compat_exact_traditional_rresvport_semantics */
371 sin.sin_port = htons((u_short)*alport);
372 if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) >= 0)
374 if (errno != EADDRINUSE) {
380 if (bindresvport_sa(s, (struct sockaddr *)&ss) == -1) {
384 *alport = (int)ntohs(*sport);
388 int __check_rhosts_file = 1;
392 ruserok(rhost, superuser, ruser, luser)
393 const char *rhost, *ruser, *luser;
396 struct addrinfo hints, *res, *r;
399 memset(&hints, 0, sizeof(hints));
400 hints.ai_family = PF_UNSPEC;
401 hints.ai_socktype = SOCK_DGRAM; /*dummy*/
402 error = getaddrinfo(rhost, "0", &hints, &res);
406 for (r = res; r; r = r->ai_next) {
407 if (iruserok_sa(r->ai_addr, r->ai_addrlen, superuser, ruser,
418 * New .rhosts strategy: We are passed an ip address. We spin through
419 * hosts.equiv and .rhosts looking for a match. When the .rhosts only
420 * has ip addresses, we don't have to trust a nameserver. When it
421 * contains hostnames, we spin through the list of addresses the nameserver
422 * gives us and look for a match.
424 * Returns 0 if ok, -1 if not ok.
427 iruserok(raddr, superuser, ruser, luser)
430 const char *ruser, *luser;
432 struct sockaddr_in sin;
434 memset(&sin, 0, sizeof(sin));
435 sin.sin_family = AF_INET;
436 sin.sin_len = sizeof(struct sockaddr_in);
437 memcpy(&sin.sin_addr, &raddr, sizeof(sin.sin_addr));
438 return iruserok_sa((struct sockaddr *)&sin, sin.sin_len, superuser,
443 * AF independent extension of iruserok.
445 * Returns 0 if ok, -1 if not ok.
448 iruserok_sa(ra, rlen, superuser, ruser, luser)
452 const char *ruser, *luser;
460 char pbuf[MAXPATHLEN];
461 const struct sockaddr *raddr;
462 struct sockaddr_storage ss;
464 /* avoid alignment issue */
465 if (rlen > sizeof(ss))
467 memcpy(&ss, ra, rlen);
468 raddr = (struct sockaddr *)&ss;
471 hostf = superuser ? NULL : fopen(_PATH_HEQUIV, "r");
474 if (__ivaliduser_sa(hostf, raddr, rlen, luser, ruser) == 0) {
480 if (first == 1 && (__check_rhosts_file || superuser)) {
482 if ((pwd = getpwnam(luser)) == NULL)
484 (void)strcpy(pbuf, pwd->pw_dir);
485 (void)strcat(pbuf, "/.rhosts");
488 * Change effective uid while opening .rhosts. If root and
489 * reading an NFS mounted file system, can't read files that
490 * are protected read/write owner only.
493 (void)seteuid(pwd->pw_uid);
494 hostf = fopen(pbuf, "r");
500 * If not a regular file, or is owned by someone other than
501 * user or root or if writeable by anyone but the owner, quit.
504 if (lstat(pbuf, &sbuf) < 0)
505 cp = ".rhosts lstat failed";
506 else if (!S_ISREG(sbuf.st_mode))
507 cp = ".rhosts not regular file";
508 else if (fstat(fileno(hostf), &sbuf) < 0)
509 cp = ".rhosts fstat failed";
510 else if (sbuf.st_uid && sbuf.st_uid != pwd->pw_uid)
511 cp = "bad .rhosts owner";
512 else if (sbuf.st_mode & (S_IWGRP|S_IWOTH))
513 cp = ".rhosts writeable by other than owner";
514 /* If there were any problems, quit. */
527 * Don't make static, used by lpd(8).
529 * Returns 0 if ok, -1 if not ok.
532 __ivaliduser(hostf, raddr, luser, ruser)
535 const char *luser, *ruser;
537 struct sockaddr_in sin;
539 memset(&sin, 0, sizeof(sin));
540 sin.sin_family = AF_INET;
541 sin.sin_len = sizeof(struct sockaddr_in);
542 memcpy(&sin.sin_addr, &raddr, sizeof(sin.sin_addr));
543 return __ivaliduser_sa(hostf, (struct sockaddr *)&sin, sin.sin_len,
548 * Returns 0 if ok, -1 if not ok.
553 __ivaliduser_af(hostf, raddr, luser, ruser, af, len)
556 const char *luser, *ruser;
559 struct sockaddr *sa = NULL;
560 struct sockaddr_in *sin = NULL;
562 struct sockaddr_in6 *sin6 = NULL;
564 struct sockaddr_storage ss;
566 memset(&ss, 0, sizeof(ss));
569 if (len != sizeof(sin->sin_addr))
571 sin = (struct sockaddr_in *)&ss;
572 sin->sin_family = AF_INET;
573 sin->sin_len = sizeof(struct sockaddr_in);
574 memcpy(&sin->sin_addr, raddr, sizeof(sin->sin_addr));
578 if (len != sizeof(sin6->sin6_addr))
580 /* you will lose scope info */
581 sin6 = (struct sockaddr_in6 *)&ss;
582 sin6->sin6_family = AF_INET6;
583 sin6->sin6_len = sizeof(struct sockaddr_in6);
584 memcpy(&sin6->sin6_addr, raddr, sizeof(sin6->sin6_addr));
591 sa = (struct sockaddr *)&ss;
592 return __ivaliduser_sa(hostf, sa, sa->sa_len, luser, ruser);
596 * Returns 0 if ok, -1 if not ok.
599 __ivaliduser_sa(hostf, raddr, salen, luser, ruser)
601 const struct sockaddr *raddr;
603 const char *luser, *ruser;
605 register char *user, *p;
607 char buf[MAXHOSTNAMELEN + 128]; /* host + login */
608 char hname[MAXHOSTNAMELEN];
609 /* Presumed guilty until proven innocent. */
610 int userok = 0, hostok = 0;
615 if (yp_get_default_domain(&ypdomain))
618 #define ypdomain NULL
620 /* We need to get the damn hostname back for netgroup matching. */
621 if (getnameinfo(raddr, salen, hname, sizeof(hname), NULL, 0,
625 while (fgets(buf, sizeof(buf), hostf)) {
627 /* Skip lines that are too long. */
628 if (strchr(p, '\n') == NULL) {
629 while ((ch = getc(hostf)) != '\n' && ch != EOF);
632 if (*p == '\n' || *p == '#') {
636 while (*p != '\n' && *p != ' ' && *p != '\t' && *p != '\0') {
637 *p = isupper((unsigned char)*p) ? tolower((unsigned char)*p) : *p;
640 if (*p == ' ' || *p == '\t') {
642 while (*p == ' ' || *p == '\t')
645 while (*p != '\n' && *p != ' ' &&
646 *p != '\t' && *p != '\0')
652 * Do +/- and +@/-@ checking. This looks really nasty,
653 * but it matches SunOS's behavior so far as I can tell.
657 if (!buf[1]) { /* '+' matches all hosts */
661 if (buf[1] == '@') /* match a host by netgroup */
662 hostok = hname[0] != '\0' &&
663 innetgr(&buf[2], hname, NULL, ypdomain);
664 else /* match a host by addr */
665 hostok = __icheckhost(raddr, salen,
668 case '-': /* reject '-' hosts and all their users */
670 if (hname[0] == '\0' ||
671 innetgr(&buf[2], hname, NULL, ypdomain))
674 if (__icheckhost(raddr, salen,
679 default: /* if no '+' or '-', do a simple match */
680 hostok = __icheckhost(raddr, salen, buf);
685 if (!*(user+1)) { /* '+' matches all users */
689 if (*(user+1) == '@') /* match a user by netgroup */
690 userok = innetgr(user+2, NULL, ruser, ypdomain);
691 else /* match a user by direct specification */
692 userok = !(strcmp(ruser, user+1));
694 case '-': /* if we matched a hostname, */
695 if (hostok) { /* check for user field rejections */
698 if (*(user+1) == '@') {
699 if (innetgr(user+2, NULL,
703 if (!strcmp(ruser, user+1))
708 default: /* no rejections: try to match the user */
710 userok = !(strcmp(ruser,*user ? user : luser));
713 if (hostok && userok)
720 * Returns "true" if match, 0 if no match.
722 * NI_WITHSCOPEID is useful for comparing sin6_scope_id portion
726 __icheckhost(raddr, salen, lhost)
727 const struct sockaddr *raddr;
731 struct sockaddr_in sin;
732 struct sockaddr_in6 *sin6;
733 struct addrinfo hints, *res, *r;
735 char h1[NI_MAXHOST], h2[NI_MAXHOST];
737 if (raddr->sa_family == AF_INET6) {
738 sin6 = (struct sockaddr_in6 *)raddr;
739 if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
740 memset(&sin, 0, sizeof(sin));
741 sin.sin_family = AF_INET;
742 sin.sin_len = sizeof(struct sockaddr_in);
743 memcpy(&sin.sin_addr, &sin6->sin6_addr.s6_addr[12],
744 sizeof(sin.sin_addr));
745 raddr = (struct sockaddr *)&sin;
751 if (getnameinfo(raddr, salen, h1, sizeof(h1), NULL, 0,
752 NI_NUMERICHOST | NI_WITHSCOPEID) != 0)
755 /* Resolve laddr into sockaddr */
756 memset(&hints, 0, sizeof(hints));
757 hints.ai_family = raddr->sa_family;
758 hints.ai_socktype = SOCK_DGRAM; /*XXX dummy*/
760 error = getaddrinfo(lhost, "0", &hints, &res);
764 for (r = res; r ; r = r->ai_next) {
766 if (getnameinfo(r->ai_addr, r->ai_addrlen, h2, sizeof(h2),
767 NULL, 0, NI_NUMERICHOST | NI_WITHSCOPEID) != 0)
769 if (strcmp(h1, h2) == 0) {