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 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 #if defined(LIBC_SCCS) && !defined(lint)
31 static char sccsid[] = "@(#)rcmd.c 8.3 (Berkeley) 3/26/94";
32 #endif /* LIBC_SCCS and not lint */
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
36 #include "namespace.h"
37 #include <sys/param.h>
38 #include <sys/socket.h>
41 #include <netinet/in.h>
42 #include <arpa/inet.h>
56 #include <rpcsvc/yp_prot.h>
57 #include <rpcsvc/ypclnt.h>
59 #include <arpa/nameser.h>
60 #include "un-namespace.h"
62 extern int innetgr( const char *, const char *, const char *, const char * );
64 #define max(a, b) ((a > b) ? a : b)
66 int __ivaliduser(FILE *, u_int32_t, const char *, const char *);
67 int __ivaliduser_af(FILE *,const void *, const char *, const char *, int, int);
68 int __ivaliduser_sa(FILE *, const struct sockaddr *, socklen_t, const char *,
70 static int __icheckhost(const struct sockaddr *, socklen_t, const char *);
72 char paddr[NI_MAXHOST];
75 rcmd(ahost, rport, locuser, remuser, cmd, fd2p)
78 const char *locuser, *remuser, *cmd;
81 return rcmd_af(ahost, rport, locuser, remuser, cmd, fd2p, AF_INET);
85 rcmd_af(ahost, rport, locuser, remuser, cmd, fd2p, af)
88 const char *locuser, *remuser, *cmd;
92 struct addrinfo hints, *res, *ai;
93 struct sockaddr_storage from;
95 sigset_t oldmask, newmask;
97 int s, aport, lport, timo, error;
101 static char canonnamebuf[MAXDNAME]; /* is it proper here? */
103 /* call rcmdsh() with specified remote shell if appropriate. */
104 if (!issetugid() && (p = getenv("RSH"))) {
105 struct servent *sp = getservbyname("shell", "tcp");
107 if (sp && sp->s_port == rport)
108 return (rcmdsh(ahost, rport, locuser, remuser,
112 /* use rsh(1) if non-root and remote port is shell. */
114 struct servent *sp = getservbyname("shell", "tcp");
116 if (sp && sp->s_port == rport)
117 return (rcmdsh(ahost, rport, locuser, remuser,
123 memset(&hints, 0, sizeof(hints));
124 hints.ai_flags = AI_CANONNAME;
125 hints.ai_family = af;
126 hints.ai_socktype = SOCK_STREAM;
127 hints.ai_protocol = 0;
128 (void)snprintf(num, sizeof(num), "%d", ntohs(rport));
129 error = getaddrinfo(*ahost, num, &hints, &res);
131 fprintf(stderr, "rcmd: getaddrinfo: %s\n",
132 gai_strerror(error));
133 if (error == EAI_SYSTEM)
134 fprintf(stderr, "rcmd: getaddrinfo: %s\n",
139 if (res->ai_canonname
140 && strlen(res->ai_canonname) + 1 < sizeof(canonnamebuf)) {
141 strncpy(canonnamebuf, res->ai_canonname, sizeof(canonnamebuf));
142 *ahost = canonnamebuf;
145 for (ai = res; ai; ai = ai->ai_next)
149 sigemptyset(&newmask);
150 sigaddset(&newmask, SIGURG);
151 _sigprocmask(SIG_BLOCK, (const sigset_t *)&newmask, &oldmask);
152 for (timo = 1, lport = IPPORT_RESERVED - 1;;) {
153 s = rresvport_af(&lport, ai->ai_family);
155 if (errno != EAGAIN && ai->ai_next) {
160 (void)fprintf(stderr,
161 "rcmd: socket: All ports in use\n");
163 (void)fprintf(stderr, "rcmd: socket: %s\n",
166 _sigprocmask(SIG_SETMASK, (const sigset_t *)&oldmask,
170 _fcntl(s, F_SETOWN, pid);
171 if (_connect(s, ai->ai_addr, ai->ai_addrlen) >= 0)
174 if (errno == EADDRINUSE) {
178 if (errno == ECONNREFUSED)
180 if (ai->ai_next == NULL && (!refused || timo > 16)) {
181 (void)fprintf(stderr, "%s: %s\n",
182 *ahost, strerror(errno));
184 _sigprocmask(SIG_SETMASK, (const sigset_t *)&oldmask,
191 getnameinfo(ai->ai_addr, ai->ai_addrlen, paddr,
192 sizeof(paddr), NULL, 0, NI_NUMERICHOST);
193 (void)fprintf(stderr, "connect to address %s: ",
198 if ((ai = ai->ai_next) == NULL) {
199 /* refused && timo <= 16 */
200 struct timespec time_to_sleep, time_remaining;
202 time_to_sleep.tv_sec = timo;
203 time_to_sleep.tv_nsec = 0;
204 (void)_nanosleep(&time_to_sleep, &time_remaining);
210 getnameinfo(ai->ai_addr, ai->ai_addrlen, paddr,
211 sizeof(paddr), NULL, 0, NI_NUMERICHOST);
212 fprintf(stderr, "Trying %s...\n", paddr);
220 int s2 = rresvport_af(&lport, ai->ai_family), s3;
221 socklen_t len = ai->ai_addrlen;
227 (void)snprintf(num, sizeof(num), "%d", lport);
228 if (_write(s, num, strlen(num)+1) != strlen(num)+1) {
229 (void)fprintf(stderr,
230 "rcmd: write (setting up stderr): %s\n",
236 if(nfds > FD_SETSIZE) {
237 fprintf(stderr, "rcmd: too many files\n");
246 if (_select(nfds, &reads, 0, 0, 0) < 1 || !FD_ISSET(s2, &reads)){
248 (void)fprintf(stderr,
249 "rcmd: select (setting up stderr): %s\n",
252 (void)fprintf(stderr,
253 "select: protocol failure in circuit setup\n");
257 s3 = _accept(s2, (struct sockaddr *)&from, &len);
258 switch (from.ss_family) {
260 aport = ntohs(((struct sockaddr_in *)&from)->sin_port);
264 aport = ntohs(((struct sockaddr_in6 *)&from)->sin6_port);
268 aport = 0; /* error */
272 * XXX careful for ftp bounce attacks. If discovered, shut them
273 * down and check for the real auxiliary channel to connect.
281 (void)fprintf(stderr,
282 "rcmd: accept: %s\n", strerror(errno));
287 if (aport >= IPPORT_RESERVED || aport < IPPORT_RESERVED / 2) {
288 (void)fprintf(stderr,
289 "socket: protocol failure in circuit setup.\n");
293 (void)_write(s, locuser, strlen(locuser)+1);
294 (void)_write(s, remuser, strlen(remuser)+1);
295 (void)_write(s, cmd, strlen(cmd)+1);
296 if (_read(s, &c, 1) != 1) {
297 (void)fprintf(stderr,
298 "rcmd: %s: %s\n", *ahost, strerror(errno));
302 while (_read(s, &c, 1) == 1) {
303 (void)_write(STDERR_FILENO, &c, 1);
309 _sigprocmask(SIG_SETMASK, (const sigset_t *)&oldmask, NULL);
317 _sigprocmask(SIG_SETMASK, (const sigset_t *)&oldmask, NULL);
326 return rresvport_af(port, AF_INET);
330 rresvport_af(alport, family)
334 struct sockaddr_storage ss;
337 memset(&ss, 0, sizeof(ss));
338 ss.ss_family = family;
341 ((struct sockaddr *)&ss)->sa_len = sizeof(struct sockaddr_in);
342 sport = &((struct sockaddr_in *)&ss)->sin_port;
343 ((struct sockaddr_in *)&ss)->sin_addr.s_addr = INADDR_ANY;
347 ((struct sockaddr *)&ss)->sa_len = sizeof(struct sockaddr_in6);
348 sport = &((struct sockaddr_in6 *)&ss)->sin6_port;
349 ((struct sockaddr_in6 *)&ss)->sin6_addr = in6addr_any;
353 errno = EAFNOSUPPORT;
357 s = _socket(ss.ss_family, SOCK_STREAM, 0);
360 #if 0 /* compat_exact_traditional_rresvport_semantics */
361 sin.sin_port = htons((u_short)*alport);
362 if (_bind(s, (struct sockaddr *)&sin, sizeof(sin)) >= 0)
364 if (errno != EADDRINUSE) {
370 if (bindresvport_sa(s, (struct sockaddr *)&ss) == -1) {
374 *alport = (int)ntohs(*sport);
378 int __check_rhosts_file = 1;
382 ruserok(rhost, superuser, ruser, luser)
383 const char *rhost, *ruser, *luser;
386 struct addrinfo hints, *res, *r;
389 memset(&hints, 0, sizeof(hints));
390 hints.ai_family = PF_UNSPEC;
391 hints.ai_socktype = SOCK_DGRAM; /*dummy*/
392 error = getaddrinfo(rhost, "0", &hints, &res);
396 for (r = res; r; r = r->ai_next) {
397 if (iruserok_sa(r->ai_addr, r->ai_addrlen, superuser, ruser,
408 * New .rhosts strategy: We are passed an ip address. We spin through
409 * hosts.equiv and .rhosts looking for a match. When the .rhosts only
410 * has ip addresses, we don't have to trust a nameserver. When it
411 * contains hostnames, we spin through the list of addresses the nameserver
412 * gives us and look for a match.
414 * Returns 0 if ok, -1 if not ok.
417 iruserok(raddr, superuser, ruser, luser)
420 const char *ruser, *luser;
422 struct sockaddr_in sin;
424 memset(&sin, 0, sizeof(sin));
425 sin.sin_family = AF_INET;
426 sin.sin_len = sizeof(struct sockaddr_in);
427 memcpy(&sin.sin_addr, &raddr, sizeof(sin.sin_addr));
428 return iruserok_sa((struct sockaddr *)&sin, sin.sin_len, superuser,
433 * AF independent extension of iruserok.
435 * Returns 0 if ok, -1 if not ok.
438 iruserok_sa(ra, rlen, superuser, ruser, luser)
442 const char *ruser, *luser;
450 char pbuf[MAXPATHLEN];
451 const struct sockaddr *raddr;
452 struct sockaddr_storage ss;
454 /* avoid alignment issue */
455 if (rlen > sizeof(ss))
457 memcpy(&ss, ra, rlen);
458 raddr = (struct sockaddr *)&ss;
461 hostf = superuser ? NULL : fopen(_PATH_HEQUIV, "re");
464 if (__ivaliduser_sa(hostf, raddr, rlen, luser, ruser) == 0) {
470 if (first == 1 && (__check_rhosts_file || superuser)) {
472 if ((pwd = getpwnam(luser)) == NULL)
474 (void)strcpy(pbuf, pwd->pw_dir);
475 (void)strcat(pbuf, "/.rhosts");
478 * Change effective uid while opening .rhosts. If root and
479 * reading an NFS mounted file system, can't read files that
480 * are protected read/write owner only.
483 (void)seteuid(pwd->pw_uid);
484 hostf = fopen(pbuf, "re");
490 * If not a regular file, or is owned by someone other than
491 * user or root or if writeable by anyone but the owner, quit.
494 if (lstat(pbuf, &sbuf) < 0)
495 cp = ".rhosts lstat failed";
496 else if (!S_ISREG(sbuf.st_mode))
497 cp = ".rhosts not regular file";
498 else if (_fstat(fileno(hostf), &sbuf) < 0)
499 cp = ".rhosts fstat failed";
500 else if (sbuf.st_uid && sbuf.st_uid != pwd->pw_uid)
501 cp = "bad .rhosts owner";
502 else if (sbuf.st_mode & (S_IWGRP|S_IWOTH))
503 cp = ".rhosts writeable by other than owner";
504 /* If there were any problems, quit. */
517 * Don't make static, used by lpd(8).
519 * Returns 0 if ok, -1 if not ok.
522 __ivaliduser(hostf, raddr, luser, ruser)
525 const char *luser, *ruser;
527 struct sockaddr_in sin;
529 memset(&sin, 0, sizeof(sin));
530 sin.sin_family = AF_INET;
531 sin.sin_len = sizeof(struct sockaddr_in);
532 memcpy(&sin.sin_addr, &raddr, sizeof(sin.sin_addr));
533 return __ivaliduser_sa(hostf, (struct sockaddr *)&sin, sin.sin_len,
538 * Returns 0 if ok, -1 if not ok.
543 __ivaliduser_af(hostf, raddr, luser, ruser, af, len)
546 const char *luser, *ruser;
549 struct sockaddr *sa = NULL;
550 struct sockaddr_in *sin = NULL;
552 struct sockaddr_in6 *sin6 = NULL;
554 struct sockaddr_storage ss;
556 memset(&ss, 0, sizeof(ss));
559 if (len != sizeof(sin->sin_addr))
561 sin = (struct sockaddr_in *)&ss;
562 sin->sin_family = AF_INET;
563 sin->sin_len = sizeof(struct sockaddr_in);
564 memcpy(&sin->sin_addr, raddr, sizeof(sin->sin_addr));
568 if (len != sizeof(sin6->sin6_addr))
570 /* you will lose scope info */
571 sin6 = (struct sockaddr_in6 *)&ss;
572 sin6->sin6_family = AF_INET6;
573 sin6->sin6_len = sizeof(struct sockaddr_in6);
574 memcpy(&sin6->sin6_addr, raddr, sizeof(sin6->sin6_addr));
581 sa = (struct sockaddr *)&ss;
582 return __ivaliduser_sa(hostf, sa, sa->sa_len, luser, ruser);
586 __ivaliduser_sa(hostf, raddr, salen, luser, ruser)
588 const struct sockaddr *raddr;
590 const char *luser, *ruser;
594 char buf[MAXHOSTNAMELEN + 128]; /* host + login */
595 char hname[MAXHOSTNAMELEN];
596 /* Presumed guilty until proven innocent. */
597 int userok = 0, hostok = 0;
601 if (yp_get_default_domain(&ypdomain))
604 #define ypdomain NULL
606 /* We need to get the damn hostname back for netgroup matching. */
607 if (getnameinfo(raddr, salen, hname, sizeof(hname), NULL, 0,
611 while (fgets(buf, sizeof(buf), hostf)) {
613 /* Skip lines that are too long. */
614 if (strchr(p, '\n') == NULL) {
615 while ((ch = getc(hostf)) != '\n' && ch != EOF);
618 if (*p == '\n' || *p == '#') {
622 while (*p != '\n' && *p != ' ' && *p != '\t' && *p != '\0') {
623 *p = isupper((unsigned char)*p) ? tolower((unsigned char)*p) : *p;
626 if (*p == ' ' || *p == '\t') {
628 while (*p == ' ' || *p == '\t')
631 while (*p != '\n' && *p != ' ' &&
632 *p != '\t' && *p != '\0')
638 * Do +/- and +@/-@ checking. This looks really nasty,
639 * but it matches SunOS's behavior so far as I can tell.
643 if (!buf[1]) { /* '+' matches all hosts */
647 if (buf[1] == '@') /* match a host by netgroup */
648 hostok = hname[0] != '\0' &&
649 innetgr(&buf[2], hname, NULL, ypdomain);
650 else /* match a host by addr */
651 hostok = __icheckhost(raddr, salen,
654 case '-': /* reject '-' hosts and all their users */
656 if (hname[0] == '\0' ||
657 innetgr(&buf[2], hname, NULL, ypdomain))
660 if (__icheckhost(raddr, salen,
665 default: /* if no '+' or '-', do a simple match */
666 hostok = __icheckhost(raddr, salen, buf);
671 if (!*(user+1)) { /* '+' matches all users */
675 if (*(user+1) == '@') /* match a user by netgroup */
676 userok = innetgr(user+2, NULL, ruser, ypdomain);
677 else /* match a user by direct specification */
678 userok = !(strcmp(ruser, user+1));
680 case '-': /* if we matched a hostname, */
681 if (hostok) { /* check for user field rejections */
684 if (*(user+1) == '@') {
685 if (innetgr(user+2, NULL,
689 if (!strcmp(ruser, user+1))
694 default: /* no rejections: try to match the user */
696 userok = !(strcmp(ruser,*user ? user : luser));
699 if (hostok && userok)
706 * Returns "true" if match, 0 if no match.
709 __icheckhost(raddr, salen, lhost)
710 const struct sockaddr *raddr;
714 struct sockaddr_in sin;
715 struct sockaddr_in6 *sin6;
716 struct addrinfo hints, *res, *r;
718 char h1[NI_MAXHOST], h2[NI_MAXHOST];
720 if (raddr->sa_family == AF_INET6) {
721 sin6 = (struct sockaddr_in6 *)raddr;
722 if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
723 memset(&sin, 0, sizeof(sin));
724 sin.sin_family = AF_INET;
725 sin.sin_len = sizeof(struct sockaddr_in);
726 memcpy(&sin.sin_addr, &sin6->sin6_addr.s6_addr[12],
727 sizeof(sin.sin_addr));
728 raddr = (struct sockaddr *)&sin;
734 if (getnameinfo(raddr, salen, h1, sizeof(h1), NULL, 0,
735 NI_NUMERICHOST) != 0)
738 /* Resolve laddr into sockaddr */
739 memset(&hints, 0, sizeof(hints));
740 hints.ai_family = raddr->sa_family;
741 hints.ai_socktype = SOCK_DGRAM; /*XXX dummy*/
743 error = getaddrinfo(lhost, "0", &hints, &res);
747 for (r = res; r ; r = r->ai_next) {
749 if (getnameinfo(r->ai_addr, r->ai_addrlen, h2, sizeof(h2),
750 NULL, 0, NI_NUMERICHOST) != 0)
752 if (strcmp(h1, h2) == 0) {