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"
61 #include "libc_private.h"
63 extern int innetgr( const char *, const char *, const char *, const char * );
65 #define max(a, b) ((a > b) ? a : b)
67 int __ivaliduser(FILE *, u_int32_t, const char *, const char *);
68 int __ivaliduser_af(FILE *,const void *, const char *, const char *, int, int);
69 int __ivaliduser_sa(FILE *, const struct sockaddr *, socklen_t, const char *,
71 static int __icheckhost(const struct sockaddr *, socklen_t, const char *);
73 char paddr[NI_MAXHOST];
76 rcmd(char **ahost, int rport, const char *locuser, const char *remuser,
77 const char *cmd, int *fd2p)
79 return rcmd_af(ahost, rport, locuser, remuser, cmd, fd2p, AF_INET);
83 rcmd_af(char **ahost, int rport, const char *locuser, const char *remuser,
84 const char *cmd, int *fd2p, int af)
86 struct addrinfo hints, *res, *ai;
87 struct sockaddr_storage from;
89 sigset_t oldmask, newmask;
91 int s, aport, lport, timo, error;
95 static char canonnamebuf[MAXDNAME]; /* is it proper here? */
97 /* call rcmdsh() with specified remote shell if appropriate. */
98 if (!issetugid() && (p = getenv("RSH"))) {
99 struct servent *sp = getservbyname("shell", "tcp");
101 if (sp && sp->s_port == rport)
102 return (rcmdsh(ahost, rport, locuser, remuser,
106 /* use rsh(1) if non-root and remote port is shell. */
108 struct servent *sp = getservbyname("shell", "tcp");
110 if (sp && sp->s_port == rport)
111 return (rcmdsh(ahost, rport, locuser, remuser,
117 memset(&hints, 0, sizeof(hints));
118 hints.ai_flags = AI_CANONNAME;
119 hints.ai_family = af;
120 hints.ai_socktype = SOCK_STREAM;
121 hints.ai_protocol = 0;
122 (void)snprintf(num, sizeof(num), "%d", ntohs(rport));
123 error = getaddrinfo(*ahost, num, &hints, &res);
125 fprintf(stderr, "rcmd: getaddrinfo: %s\n",
126 gai_strerror(error));
127 if (error == EAI_SYSTEM)
128 fprintf(stderr, "rcmd: getaddrinfo: %s\n",
133 if (res->ai_canonname
134 && strlen(res->ai_canonname) + 1 < sizeof(canonnamebuf)) {
135 strncpy(canonnamebuf, res->ai_canonname, sizeof(canonnamebuf));
136 *ahost = canonnamebuf;
139 for (ai = res; ai; ai = ai->ai_next)
143 sigemptyset(&newmask);
144 sigaddset(&newmask, SIGURG);
145 __libc_sigprocmask(SIG_BLOCK, (const sigset_t *)&newmask, &oldmask);
146 for (timo = 1, lport = IPPORT_RESERVED - 1;;) {
147 s = rresvport_af(&lport, ai->ai_family);
149 if (errno != EAGAIN && ai->ai_next) {
154 (void)fprintf(stderr,
155 "rcmd: socket: All ports in use\n");
157 (void)fprintf(stderr, "rcmd: socket: %s\n",
160 __libc_sigprocmask(SIG_SETMASK, (const sigset_t *)&oldmask,
164 _fcntl(s, F_SETOWN, pid);
165 if (_connect(s, ai->ai_addr, ai->ai_addrlen) >= 0)
168 if (errno == EADDRINUSE) {
172 if (errno == ECONNREFUSED)
174 if (ai->ai_next == NULL && (!refused || timo > 16)) {
175 (void)fprintf(stderr, "%s: %s\n",
176 *ahost, strerror(errno));
178 __libc_sigprocmask(SIG_SETMASK, (const sigset_t *)&oldmask,
185 getnameinfo(ai->ai_addr, ai->ai_addrlen, paddr,
186 sizeof(paddr), NULL, 0, NI_NUMERICHOST);
187 (void)fprintf(stderr, "connect to address %s: ",
192 if ((ai = ai->ai_next) == NULL) {
193 /* refused && timo <= 16 */
194 struct timespec time_to_sleep, time_remaining;
196 time_to_sleep.tv_sec = timo;
197 time_to_sleep.tv_nsec = 0;
198 (void)_nanosleep(&time_to_sleep, &time_remaining);
204 getnameinfo(ai->ai_addr, ai->ai_addrlen, paddr,
205 sizeof(paddr), NULL, 0, NI_NUMERICHOST);
206 fprintf(stderr, "Trying %s...\n", paddr);
214 int s2 = rresvport_af(&lport, ai->ai_family), s3;
215 socklen_t len = ai->ai_addrlen;
221 (void)snprintf(num, sizeof(num), "%d", lport);
222 if (_write(s, num, strlen(num)+1) != strlen(num)+1) {
223 (void)fprintf(stderr,
224 "rcmd: write (setting up stderr): %s\n",
230 if(nfds > FD_SETSIZE) {
231 fprintf(stderr, "rcmd: too many files\n");
240 if (_select(nfds, &reads, 0, 0, 0) < 1 || !FD_ISSET(s2, &reads)){
242 (void)fprintf(stderr,
243 "rcmd: select (setting up stderr): %s\n",
246 (void)fprintf(stderr,
247 "select: protocol failure in circuit setup\n");
251 s3 = _accept(s2, (struct sockaddr *)&from, &len);
252 switch (from.ss_family) {
254 aport = ntohs(((struct sockaddr_in *)&from)->sin_port);
258 aport = ntohs(((struct sockaddr_in6 *)&from)->sin6_port);
262 aport = 0; /* error */
266 * XXX careful for ftp bounce attacks. If discovered, shut them
267 * down and check for the real auxiliary channel to connect.
275 (void)fprintf(stderr,
276 "rcmd: accept: %s\n", strerror(errno));
281 if (aport >= IPPORT_RESERVED || aport < IPPORT_RESERVED / 2) {
282 (void)fprintf(stderr,
283 "socket: protocol failure in circuit setup.\n");
287 (void)_write(s, locuser, strlen(locuser)+1);
288 (void)_write(s, remuser, strlen(remuser)+1);
289 (void)_write(s, cmd, strlen(cmd)+1);
290 if (_read(s, &c, 1) != 1) {
291 (void)fprintf(stderr,
292 "rcmd: %s: %s\n", *ahost, strerror(errno));
296 while (_read(s, &c, 1) == 1) {
297 (void)_write(STDERR_FILENO, &c, 1);
303 __libc_sigprocmask(SIG_SETMASK, (const sigset_t *)&oldmask, NULL);
311 __libc_sigprocmask(SIG_SETMASK, (const sigset_t *)&oldmask, NULL);
319 return rresvport_af(port, AF_INET);
323 rresvport_af(int *alport, int family)
326 struct sockaddr_storage ss;
329 memset(&ss, 0, sizeof(ss));
330 ss.ss_family = family;
333 ((struct sockaddr *)&ss)->sa_len = sizeof(struct sockaddr_in);
334 sport = &((struct sockaddr_in *)&ss)->sin_port;
335 ((struct sockaddr_in *)&ss)->sin_addr.s_addr = INADDR_ANY;
339 ((struct sockaddr *)&ss)->sa_len = sizeof(struct sockaddr_in6);
340 sport = &((struct sockaddr_in6 *)&ss)->sin6_port;
341 ((struct sockaddr_in6 *)&ss)->sin6_addr = in6addr_any;
345 errno = EAFNOSUPPORT;
349 s = _socket(ss.ss_family, SOCK_STREAM, 0);
352 #if 0 /* compat_exact_traditional_rresvport_semantics */
353 sin.sin_port = htons((u_short)*alport);
354 if (_bind(s, (struct sockaddr *)&sin, sizeof(sin)) >= 0)
356 if (errno != EADDRINUSE) {
362 if (bindresvport_sa(s, (struct sockaddr *)&ss) == -1) {
366 *alport = (int)ntohs(*sport);
370 int __check_rhosts_file = 1;
374 ruserok(const char *rhost, int superuser, const char *ruser, const char *luser)
376 struct addrinfo hints, *res, *r;
379 memset(&hints, 0, sizeof(hints));
380 hints.ai_family = PF_UNSPEC;
381 hints.ai_socktype = SOCK_DGRAM; /*dummy*/
382 error = getaddrinfo(rhost, "0", &hints, &res);
386 for (r = res; r; r = r->ai_next) {
387 if (iruserok_sa(r->ai_addr, r->ai_addrlen, superuser, ruser,
398 * New .rhosts strategy: We are passed an ip address. We spin through
399 * hosts.equiv and .rhosts looking for a match. When the .rhosts only
400 * has ip addresses, we don't have to trust a nameserver. When it
401 * contains hostnames, we spin through the list of addresses the nameserver
402 * gives us and look for a match.
404 * Returns 0 if ok, -1 if not ok.
407 iruserok(unsigned long raddr, int superuser, const char *ruser, const char *luser)
409 struct sockaddr_in sin;
411 memset(&sin, 0, sizeof(sin));
412 sin.sin_family = AF_INET;
413 sin.sin_len = sizeof(struct sockaddr_in);
414 memcpy(&sin.sin_addr, &raddr, sizeof(sin.sin_addr));
415 return iruserok_sa((struct sockaddr *)&sin, sin.sin_len, superuser,
420 * AF independent extension of iruserok.
422 * Returns 0 if ok, -1 if not ok.
425 iruserok_sa(const void *ra, int rlen, int superuser, const char *ruser,
434 char pbuf[MAXPATHLEN];
435 const struct sockaddr *raddr;
436 struct sockaddr_storage ss;
438 /* avoid alignment issue */
439 if (rlen > sizeof(ss))
441 memcpy(&ss, ra, rlen);
442 raddr = (struct sockaddr *)&ss;
445 hostf = superuser ? NULL : fopen(_PATH_HEQUIV, "re");
448 if (__ivaliduser_sa(hostf, raddr, rlen, luser, ruser) == 0) {
454 if (first == 1 && (__check_rhosts_file || superuser)) {
456 if ((pwd = getpwnam(luser)) == NULL)
458 (void)strcpy(pbuf, pwd->pw_dir);
459 (void)strcat(pbuf, "/.rhosts");
462 * Change effective uid while opening .rhosts. If root and
463 * reading an NFS mounted file system, can't read files that
464 * are protected read/write owner only.
467 (void)seteuid(pwd->pw_uid);
468 hostf = fopen(pbuf, "re");
474 * If not a regular file, or is owned by someone other than
475 * user or root or if writeable by anyone but the owner, quit.
478 if (lstat(pbuf, &sbuf) < 0)
479 cp = ".rhosts lstat failed";
480 else if (!S_ISREG(sbuf.st_mode))
481 cp = ".rhosts not regular file";
482 else if (_fstat(fileno(hostf), &sbuf) < 0)
483 cp = ".rhosts fstat failed";
484 else if (sbuf.st_uid && sbuf.st_uid != pwd->pw_uid)
485 cp = "bad .rhosts owner";
486 else if (sbuf.st_mode & (S_IWGRP|S_IWOTH))
487 cp = ".rhosts writeable by other than owner";
488 /* If there were any problems, quit. */
501 * Don't make static, used by lpd(8).
503 * Returns 0 if ok, -1 if not ok.
506 __ivaliduser(FILE *hostf, u_int32_t raddr, const char *luser, const char *ruser)
508 struct sockaddr_in sin;
510 memset(&sin, 0, sizeof(sin));
511 sin.sin_family = AF_INET;
512 sin.sin_len = sizeof(struct sockaddr_in);
513 memcpy(&sin.sin_addr, &raddr, sizeof(sin.sin_addr));
514 return __ivaliduser_sa(hostf, (struct sockaddr *)&sin, sin.sin_len,
519 * Returns 0 if ok, -1 if not ok.
524 __ivaliduser_af(FILE *hostf, const void *raddr, const char *luser,
525 const char *ruser, int af, int len)
527 struct sockaddr *sa = NULL;
528 struct sockaddr_in *sin = NULL;
530 struct sockaddr_in6 *sin6 = NULL;
532 struct sockaddr_storage ss;
534 memset(&ss, 0, sizeof(ss));
537 if (len != sizeof(sin->sin_addr))
539 sin = (struct sockaddr_in *)&ss;
540 sin->sin_family = AF_INET;
541 sin->sin_len = sizeof(struct sockaddr_in);
542 memcpy(&sin->sin_addr, raddr, sizeof(sin->sin_addr));
546 if (len != sizeof(sin6->sin6_addr))
548 /* you will lose scope info */
549 sin6 = (struct sockaddr_in6 *)&ss;
550 sin6->sin6_family = AF_INET6;
551 sin6->sin6_len = sizeof(struct sockaddr_in6);
552 memcpy(&sin6->sin6_addr, raddr, sizeof(sin6->sin6_addr));
559 sa = (struct sockaddr *)&ss;
560 return __ivaliduser_sa(hostf, sa, sa->sa_len, luser, ruser);
564 __ivaliduser_sa(FILE *hostf, const struct sockaddr *raddr, socklen_t salen,
565 const char *luser, const char *ruser)
569 char buf[MAXHOSTNAMELEN + 128]; /* host + login */
570 char hname[MAXHOSTNAMELEN];
571 /* Presumed guilty until proven innocent. */
572 int userok = 0, hostok = 0;
576 if (yp_get_default_domain(&ypdomain))
579 #define ypdomain NULL
581 /* We need to get the damn hostname back for netgroup matching. */
582 if (getnameinfo(raddr, salen, hname, sizeof(hname), NULL, 0,
586 while (fgets(buf, sizeof(buf), hostf)) {
588 /* Skip lines that are too long. */
589 if (strchr(p, '\n') == NULL) {
590 while ((ch = getc(hostf)) != '\n' && ch != EOF);
593 if (*p == '\n' || *p == '#') {
597 while (*p != '\n' && *p != ' ' && *p != '\t' && *p != '\0') {
598 *p = isupper((unsigned char)*p) ? tolower((unsigned char)*p) : *p;
601 if (*p == ' ' || *p == '\t') {
603 while (*p == ' ' || *p == '\t')
606 while (*p != '\n' && *p != ' ' &&
607 *p != '\t' && *p != '\0')
613 * Do +/- and +@/-@ checking. This looks really nasty,
614 * but it matches SunOS's behavior so far as I can tell.
618 if (!buf[1]) { /* '+' matches all hosts */
622 if (buf[1] == '@') /* match a host by netgroup */
623 hostok = hname[0] != '\0' &&
624 innetgr(&buf[2], hname, NULL, ypdomain);
625 else /* match a host by addr */
626 hostok = __icheckhost(raddr, salen,
629 case '-': /* reject '-' hosts and all their users */
631 if (hname[0] == '\0' ||
632 innetgr(&buf[2], hname, NULL, ypdomain))
635 if (__icheckhost(raddr, salen,
640 default: /* if no '+' or '-', do a simple match */
641 hostok = __icheckhost(raddr, salen, buf);
646 if (!*(user+1)) { /* '+' matches all users */
650 if (*(user+1) == '@') /* match a user by netgroup */
651 userok = innetgr(user+2, NULL, ruser, ypdomain);
652 else /* match a user by direct specification */
653 userok = !(strcmp(ruser, user+1));
655 case '-': /* if we matched a hostname, */
656 if (hostok) { /* check for user field rejections */
659 if (*(user+1) == '@') {
660 if (innetgr(user+2, NULL,
664 if (!strcmp(ruser, user+1))
669 default: /* no rejections: try to match the user */
671 userok = !(strcmp(ruser,*user ? user : luser));
674 if (hostok && userok)
681 * Returns "true" if match, 0 if no match.
684 __icheckhost(const struct sockaddr *raddr, socklen_t salen, const char *lhost)
686 struct sockaddr_in sin;
687 struct sockaddr_in6 *sin6;
688 struct addrinfo hints, *res, *r;
690 char h1[NI_MAXHOST], h2[NI_MAXHOST];
692 if (raddr->sa_family == AF_INET6) {
693 sin6 = (struct sockaddr_in6 *)raddr;
694 if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
695 memset(&sin, 0, sizeof(sin));
696 sin.sin_family = AF_INET;
697 sin.sin_len = sizeof(struct sockaddr_in);
698 memcpy(&sin.sin_addr, &sin6->sin6_addr.s6_addr[12],
699 sizeof(sin.sin_addr));
700 raddr = (struct sockaddr *)&sin;
706 if (getnameinfo(raddr, salen, h1, sizeof(h1), NULL, 0,
707 NI_NUMERICHOST) != 0)
710 /* Resolve laddr into sockaddr */
711 memset(&hints, 0, sizeof(hints));
712 hints.ai_family = raddr->sa_family;
713 hints.ai_socktype = SOCK_DGRAM; /*XXX dummy*/
715 error = getaddrinfo(lhost, "0", &hints, &res);
719 for (r = res; r ; r = r->ai_next) {
721 if (getnameinfo(r->ai_addr, r->ai_addrlen, h2, sizeof(h2),
722 NULL, 0, NI_NUMERICHOST) != 0)
724 if (strcmp(h1, h2) == 0) {