rsh.c revision 120945 
1/*
2 * Copyright (c) 1997 - 2003 Kungliga Tekniska H�gskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * 3. Neither the name of the Institute 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.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE 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 INSTITUTE 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
31 * SUCH DAMAGE.
32 */
33
34#include "rsh_locl.h"
35RCSID("$Id: rsh.c,v 1.71 2003/04/16 20:37:20 joda Exp $");
36
37enum auth_method auth_method;
38#if defined(KRB4) || defined(KRB5)
39int do_encrypt       = -1;
40#endif
41#ifdef KRB5
42int do_unique_tkfile = 0;
43char *unique_tkfile  = NULL;
44char tkfile[MAXPATHLEN];
45int do_forward       = -1;
46int do_forwardable   = -1;
47krb5_context context;
48krb5_keyblock *keyblock;
49krb5_crypto crypto;
50#endif
51#ifdef KRB4
52des_key_schedule schedule;
53des_cblock iv;
54#endif
55int sock_debug	     = 0;
56
57#ifdef KRB4
58static int use_v4 = -1;
59#endif
60#ifdef KRB5
61static int use_v5 = -1;
62#endif
63static int use_only_broken = 0;
64static int use_broken = 1;
65static char *port_str;
66static const char *user;
67static int do_version;
68static int do_help;
69static int do_errsock = 1;
70static char *protocol_version_str;
71static int protocol_version = 2;
72
73/*
74 *
75 */
76
77static int input = 1;		/* Read from stdin */
78
79static int
80loop (int s, int errsock)
81{
82    fd_set real_readset;
83    int count = 1;
84
85#ifdef KRB5
86    if(auth_method == AUTH_KRB5 && protocol_version == 2)
87	init_ivecs(1);
88#endif
89
90    if (s >= FD_SETSIZE || (errsock != -1 && errsock >= FD_SETSIZE))
91	errx (1, "fd too large");
92
93    FD_ZERO(&real_readset);
94    FD_SET(s, &real_readset);
95    if (errsock != -1) {
96	FD_SET(errsock, &real_readset);
97	++count;
98    }
99    if(input)
100	FD_SET(STDIN_FILENO, &real_readset);
101
102    for (;;) {
103	int ret;
104	fd_set readset;
105	char buf[RSH_BUFSIZ];
106
107	readset = real_readset;
108	ret = select (max(s, errsock) + 1, &readset, NULL, NULL, NULL);
109	if (ret < 0) {
110	    if (errno == EINTR)
111		continue;
112	    else
113		err (1, "select");
114	}
115	if (FD_ISSET(s, &readset)) {
116	    ret = do_read (s, buf, sizeof(buf), ivec_in[0]);
117	    if (ret < 0)
118		err (1, "read");
119	    else if (ret == 0) {
120		close (s);
121		FD_CLR(s, &real_readset);
122		if (--count == 0)
123		    return 0;
124	    } else
125		net_write (STDOUT_FILENO, buf, ret);
126	}
127	if (errsock != -1 && FD_ISSET(errsock, &readset)) {
128	    ret = do_read (errsock, buf, sizeof(buf), ivec_in[1]);
129	    if (ret < 0)
130		err (1, "read");
131	    else if (ret == 0) {
132		close (errsock);
133		FD_CLR(errsock, &real_readset);
134		if (--count == 0)
135		    return 0;
136	    } else
137		net_write (STDERR_FILENO, buf, ret);
138	}
139	if (FD_ISSET(STDIN_FILENO, &readset)) {
140	    ret = read (STDIN_FILENO, buf, sizeof(buf));
141	    if (ret < 0)
142		err (1, "read");
143	    else if (ret == 0) {
144		close (STDIN_FILENO);
145		FD_CLR(STDIN_FILENO, &real_readset);
146		shutdown (s, SHUT_WR);
147	    } else
148		do_write (s, buf, ret, ivec_out[0]);
149	}
150    }
151}
152
153#ifdef KRB4
154static int
155send_krb4_auth(int s,
156	       struct sockaddr *thisaddr,
157	       struct sockaddr *thataddr,
158	       const char *hostname,
159	       const char *remote_user,
160	       const char *local_user,
161	       size_t cmd_len,
162	       const char *cmd)
163{
164    KTEXT_ST text;
165    CREDENTIALS cred;
166    MSG_DAT msg;
167    int status;
168    size_t len;
169
170    /* the normal default for krb4 should be to disable encryption */
171    status = krb_sendauth ((do_encrypt == 1) ? KOPT_DO_MUTUAL : 0,
172			   s, &text, "rcmd",
173			   (char *)hostname, krb_realmofhost (hostname),
174			   getpid(), &msg, &cred, schedule,
175			   (struct sockaddr_in *)thisaddr,
176			   (struct sockaddr_in *)thataddr,
177			   KCMD_OLD_VERSION);
178    if (status != KSUCCESS) {
179	warnx("%s: %s", hostname, krb_get_err_text(status));
180	return 1;
181    }
182    memcpy (iv, cred.session, sizeof(iv));
183
184    len = strlen(remote_user) + 1;
185    if (net_write (s, remote_user, len) != len) {
186	warn("write");
187	return 1;
188    }
189    if (net_write (s, cmd, cmd_len) != cmd_len) {
190	warn("write");
191	return 1;
192    }
193    return 0;
194}
195#endif /* KRB4 */
196
197#ifdef KRB5
198/*
199 * Send forward information on `s' for host `hostname', them being
200 * forwardable themselves if `forwardable'
201 */
202
203static int
204krb5_forward_cred (krb5_auth_context auth_context,
205		   int s,
206		   const char *hostname,
207		   int forwardable)
208{
209    krb5_error_code ret;
210    krb5_ccache     ccache;
211    krb5_creds      creds;
212    krb5_kdc_flags  flags;
213    krb5_data       out_data;
214    krb5_principal  principal;
215
216    memset (&creds, 0, sizeof(creds));
217
218    ret = krb5_cc_default (context, &ccache);
219    if (ret) {
220	warnx ("could not forward creds: krb5_cc_default: %s",
221	       krb5_get_err_text (context, ret));
222	return 1;
223    }
224
225    ret = krb5_cc_get_principal (context, ccache, &principal);
226    if (ret) {
227	warnx ("could not forward creds: krb5_cc_get_principal: %s",
228	       krb5_get_err_text (context, ret));
229	return 1;
230    }
231
232    creds.client = principal;
233
234    ret = krb5_build_principal (context,
235				&creds.server,
236				strlen(principal->realm),
237				principal->realm,
238				"krbtgt",
239				principal->realm,
240				NULL);
241
242    if (ret) {
243	warnx ("could not forward creds: krb5_build_principal: %s",
244	       krb5_get_err_text (context, ret));
245	return 1;
246    }
247
248    creds.times.endtime = 0;
249
250    flags.i = 0;
251    flags.b.forwarded   = 1;
252    flags.b.forwardable = forwardable;
253
254    ret = krb5_get_forwarded_creds (context,
255				    auth_context,
256				    ccache,
257				    flags.i,
258				    hostname,
259				    &creds,
260				    &out_data);
261    if (ret) {
262	warnx ("could not forward creds: krb5_get_forwarded_creds: %s",
263	       krb5_get_err_text (context, ret));
264	return 1;
265    }
266
267    ret = krb5_write_message (context,
268			      (void *)&s,
269			      &out_data);
270    krb5_data_free (&out_data);
271
272    if (ret)
273	warnx ("could not forward creds: krb5_write_message: %s",
274	       krb5_get_err_text (context, ret));
275    return 0;
276}
277
278static int sendauth_version_error;
279
280static int
281send_krb5_auth(int s,
282	       struct sockaddr *thisaddr,
283	       struct sockaddr *thataddr,
284	       const char *hostname,
285	       const char *remote_user,
286	       const char *local_user,
287	       size_t cmd_len,
288	       const char *cmd)
289{
290    krb5_principal server;
291    krb5_data cksum_data;
292    int status;
293    size_t len;
294    krb5_auth_context auth_context = NULL;
295    const char *protocol_string = NULL;
296    krb5_flags ap_opts;
297
298    status = krb5_sname_to_principal(context,
299				     hostname,
300				     "host",
301				     KRB5_NT_SRV_HST,
302				     &server);
303    if (status) {
304	warnx ("%s: %s", hostname, krb5_get_err_text(context, status));
305	return 1;
306    }
307
308    if(do_encrypt == -1) {
309	krb5_appdefault_boolean(context, NULL,
310				krb5_principal_get_realm(context, server),
311				"encrypt",
312				FALSE,
313				&do_encrypt);
314    }
315
316    cksum_data.length = asprintf ((char **)&cksum_data.data,
317				  "%u:%s%s%s",
318				  ntohs(socket_get_port(thataddr)),
319				  do_encrypt ? "-x " : "",
320				  cmd,
321				  remote_user);
322
323    ap_opts = 0;
324
325    if(do_encrypt)
326	ap_opts |= AP_OPTS_MUTUAL_REQUIRED;
327
328    switch(protocol_version) {
329    case 2:
330	ap_opts |= AP_OPTS_USE_SUBKEY;
331	protocol_string = KCMD_NEW_VERSION;
332	break;
333    case 1:
334	protocol_string = KCMD_OLD_VERSION;
335	key_usage = KRB5_KU_OTHER_ENCRYPTED;
336	break;
337    default:
338	abort();
339    }
340
341    status = krb5_sendauth (context,
342			    &auth_context,
343			    &s,
344			    protocol_string,
345			    NULL,
346			    server,
347			    ap_opts,
348			    &cksum_data,
349			    NULL,
350			    NULL,
351			    NULL,
352			    NULL,
353			    NULL);
354
355    /* do this while we have a principal */
356    if(do_forward == -1 || do_forwardable == -1) {
357	krb5_const_realm realm = krb5_principal_get_realm(context, server);
358	if (do_forwardable == -1)
359	    krb5_appdefault_boolean(context, NULL, realm,
360				    "forwardable", FALSE,
361				    &do_forwardable);
362	if (do_forward == -1)
363	    krb5_appdefault_boolean(context, NULL, realm,
364				    "forward", FALSE,
365				    &do_forward);
366    }
367
368    krb5_free_principal(context, server);
369    krb5_data_free(&cksum_data);
370
371    if (status) {
372	if(status == KRB5_SENDAUTH_REJECTED &&
373	   protocol_version == 2 && protocol_version_str == NULL)
374	    sendauth_version_error = 1;
375	else
376	    krb5_warn(context, status, "%s", hostname);
377	return 1;
378    }
379
380    status = krb5_auth_con_getlocalsubkey (context, auth_context, &keyblock);
381    if(keyblock == NULL)
382	status = krb5_auth_con_getkey (context, auth_context, &keyblock);
383    if (status) {
384	warnx ("krb5_auth_con_getkey: %s", krb5_get_err_text(context, status));
385	return 1;
386    }
387
388    status = krb5_auth_con_setaddrs_from_fd (context,
389					     auth_context,
390					     &s);
391    if (status) {
392        warnx("krb5_auth_con_setaddrs_from_fd: %s",
393	      krb5_get_err_text(context, status));
394        return(1);
395    }
396
397    status = krb5_crypto_init(context, keyblock, 0, &crypto);
398    if(status) {
399	warnx ("krb5_crypto_init: %s", krb5_get_err_text(context, status));
400	return 1;
401    }
402
403    len = strlen(remote_user) + 1;
404    if (net_write (s, remote_user, len) != len) {
405	warn ("write");
406	return 1;
407    }
408    if (do_encrypt && net_write (s, "-x ", 3) != 3) {
409	warn ("write");
410	return 1;
411    }
412    if (net_write (s, cmd, cmd_len) != cmd_len) {
413	warn ("write");
414	return 1;
415    }
416
417    if (do_unique_tkfile) {
418	if (net_write (s, tkfile, strlen(tkfile)) != strlen(tkfile)) {
419	    warn ("write");
420	    return 1;
421	}
422    }
423    len = strlen(local_user) + 1;
424    if (net_write (s, local_user, len) != len) {
425	warn ("write");
426	return 1;
427    }
428
429    if (!do_forward
430	|| krb5_forward_cred (auth_context, s, hostname, do_forwardable)) {
431	/* Empty forwarding info */
432
433	u_char zero[4] = {0, 0, 0, 0};
434	write (s, &zero, 4);
435    }
436    krb5_auth_con_free (context, auth_context);
437    return 0;
438}
439
440#endif /* KRB5 */
441
442static int
443send_broken_auth(int s,
444		 struct sockaddr *thisaddr,
445		 struct sockaddr *thataddr,
446		 const char *hostname,
447		 const char *remote_user,
448		 const char *local_user,
449		 size_t cmd_len,
450		 const char *cmd)
451{
452    size_t len;
453
454    len = strlen(local_user) + 1;
455    if (net_write (s, local_user, len) != len) {
456	warn ("write");
457	return 1;
458    }
459    len = strlen(remote_user) + 1;
460    if (net_write (s, remote_user, len) != len) {
461	warn ("write");
462	return 1;
463    }
464    if (net_write (s, cmd, cmd_len) != cmd_len) {
465	warn ("write");
466	return 1;
467    }
468    return 0;
469}
470
471static int
472proto (int s, int errsock,
473       const char *hostname, const char *local_user, const char *remote_user,
474       const char *cmd, size_t cmd_len,
475       int (*auth_func)(int s,
476			struct sockaddr *this, struct sockaddr *that,
477			const char *hostname, const char *remote_user,
478			const char *local_user, size_t cmd_len,
479			const char *cmd))
480{
481    int errsock2;
482    char buf[BUFSIZ];
483    char *p;
484    size_t len;
485    char reply;
486    struct sockaddr_storage thisaddr_ss;
487    struct sockaddr *thisaddr = (struct sockaddr *)&thisaddr_ss;
488    struct sockaddr_storage thataddr_ss;
489    struct sockaddr *thataddr = (struct sockaddr *)&thataddr_ss;
490    struct sockaddr_storage erraddr_ss;
491    struct sockaddr *erraddr = (struct sockaddr *)&erraddr_ss;
492    socklen_t addrlen;
493    int ret;
494
495    addrlen = sizeof(thisaddr_ss);
496    if (getsockname (s, thisaddr, &addrlen) < 0) {
497	warn ("getsockname(%s)", hostname);
498	return 1;
499    }
500    addrlen = sizeof(thataddr_ss);
501    if (getpeername (s, thataddr, &addrlen) < 0) {
502	warn ("getpeername(%s)", hostname);
503	return 1;
504    }
505
506    if (errsock != -1) {
507
508	addrlen = sizeof(erraddr_ss);
509	if (getsockname (errsock, erraddr, &addrlen) < 0) {
510	    warn ("getsockname");
511	    return 1;
512	}
513
514	if (listen (errsock, 1) < 0) {
515	    warn ("listen");
516	    return 1;
517	}
518
519	p = buf;
520	snprintf (p, sizeof(buf), "%u",
521		  ntohs(socket_get_port(erraddr)));
522	len = strlen(buf) + 1;
523	if(net_write (s, buf, len) != len) {
524	    warn ("write");
525	    close (errsock);
526	    return 1;
527	}
528
529
530	for (;;) {
531	    fd_set fdset;
532
533	    if (errsock >= FD_SETSIZE || s >= FD_SETSIZE)
534		errx (1, "fd too large");
535
536	    FD_ZERO(&fdset);
537	    FD_SET(errsock, &fdset);
538	    FD_SET(s, &fdset);
539
540	    ret = select (max(errsock, s) + 1, &fdset, NULL, NULL, NULL);
541	    if (ret < 0) {
542		if (errno == EINTR)
543		    continue;
544		warn ("select");
545		close (errsock);
546		return 1;
547	    }
548	    if (FD_ISSET(errsock, &fdset)) {
549		errsock2 = accept (errsock, NULL, NULL);
550		close (errsock);
551		if (errsock2 < 0) {
552		    warn ("accept");
553		    return 1;
554		}
555		break;
556	    }
557
558	    /*
559	     * there should not arrive any data on this fd so if it's
560	     * readable it probably indicates that the other side when
561	     * away.
562	     */
563
564	    if (FD_ISSET(s, &fdset)) {
565		warnx ("socket closed");
566		close (errsock);
567		errsock2 = -1;
568		break;
569	    }
570	}
571    } else {
572	if (net_write (s, "0", 2) != 2) {
573	    warn ("write");
574	    return 1;
575	}
576	errsock2 = -1;
577    }
578
579    if ((*auth_func)(s, thisaddr, thataddr, hostname,
580		     remote_user, local_user,
581		     cmd_len, cmd)) {
582	close (errsock2);
583	return 1;
584    }
585
586    ret = net_read (s, &reply, 1);
587    if (ret < 0) {
588	warn ("read");
589	close (errsock2);
590	return 1;
591    } else if (ret == 0) {
592	warnx ("unexpected EOF from %s", hostname);
593	close (errsock2);
594	return 1;
595    }
596    if (reply != 0) {
597
598	warnx ("Error from rshd at %s:", hostname);
599
600	while ((ret = read (s, buf, sizeof(buf))) > 0)
601	    write (STDOUT_FILENO, buf, ret);
602        write (STDOUT_FILENO,"\n",1);
603	close (errsock2);
604	return 1;
605    }
606
607    if (sock_debug) {
608	int one = 1;
609	if (setsockopt(s, SOL_SOCKET, SO_DEBUG, (void *)&one, sizeof(one)) < 0)
610	    warn("setsockopt remote");
611	if (errsock2 != -1 &&
612	    setsockopt(errsock2, SOL_SOCKET, SO_DEBUG,
613		       (void *)&one, sizeof(one)) < 0)
614	    warn("setsockopt stderr");
615    }
616
617    return loop (s, errsock2);
618}
619
620/*
621 * Return in `res' a copy of the concatenation of `argc, argv' into
622 * malloced space.  */
623
624static size_t
625construct_command (char **res, int argc, char **argv)
626{
627    int i;
628    size_t len = 0;
629    char *tmp;
630
631    for (i = 0; i < argc; ++i)
632	len += strlen(argv[i]) + 1;
633    len = max (1, len);
634    tmp = malloc (len);
635    if (tmp == NULL)
636	errx (1, "malloc %u failed", len);
637
638    *tmp = '\0';
639    for (i = 0; i < argc - 1; ++i) {
640	strcat (tmp, argv[i]);
641	strcat (tmp, " ");
642    }
643    if (argc > 0)
644	strcat (tmp, argv[argc-1]);
645    *res = tmp;
646    return len;
647}
648
649static char *
650print_addr (const struct sockaddr *sa)
651{
652    char addr_str[256];
653    char *res;
654    const char *as = NULL;
655
656    if(sa->sa_family == AF_INET)
657	as = inet_ntop (sa->sa_family, &((struct sockaddr_in*)sa)->sin_addr,
658			addr_str, sizeof(addr_str));
659#ifdef HAVE_INET6
660    else if(sa->sa_family == AF_INET6)
661	as = inet_ntop (sa->sa_family, &((struct sockaddr_in6*)sa)->sin6_addr,
662			addr_str, sizeof(addr_str));
663#endif
664    if(as == NULL)
665	return NULL;
666    res = strdup(as);
667    if (res == NULL)
668	errx (1, "malloc: out of memory");
669    return res;
670}
671
672static int
673doit_broken (int argc,
674	     char **argv,
675	     int hostindex,
676	     struct addrinfo *ai,
677	     const char *remote_user,
678	     const char *local_user,
679	     int priv_socket1,
680	     int priv_socket2,
681	     const char *cmd,
682	     size_t cmd_len)
683{
684    struct addrinfo *a;
685
686    if (connect (priv_socket1, ai->ai_addr, ai->ai_addrlen) < 0) {
687	int save_errno = errno;
688
689	close(priv_socket1);
690	close(priv_socket2);
691
692	for (a = ai->ai_next; a != NULL; a = a->ai_next) {
693	    pid_t pid;
694	    char *adr = print_addr(a->ai_addr);
695	    if(adr == NULL)
696		continue;
697
698	    pid = fork();
699	    if (pid < 0)
700		err (1, "fork");
701	    else if(pid == 0) {
702		char **new_argv;
703		int i = 0;
704
705		new_argv = malloc((argc + 2) * sizeof(*new_argv));
706		if (new_argv == NULL)
707		    errx (1, "malloc: out of memory");
708		new_argv[i] = argv[i];
709		++i;
710		if (hostindex == i)
711		    new_argv[i++] = adr;
712		new_argv[i++] = "-K";
713		for(; i <= argc; ++i)
714		    new_argv[i] = argv[i - 1];
715		if (hostindex > 1)
716		    new_argv[hostindex + 1] = adr;
717		new_argv[argc + 1] = NULL;
718		execv(PATH_RSH, new_argv);
719		err(1, "execv(%s)", PATH_RSH);
720	    } else {
721		int status;
722		free(adr);
723
724		while(waitpid(pid, &status, 0) < 0)
725		    ;
726		if(WIFEXITED(status) && WEXITSTATUS(status) == 0)
727		    return 0;
728	    }
729	}
730	errno = save_errno;
731	warn("%s", argv[hostindex]);
732	return 1;
733    } else {
734	int ret;
735
736	ret = proto (priv_socket1, priv_socket2,
737		     argv[hostindex],
738		     local_user, remote_user,
739		     cmd, cmd_len,
740		     send_broken_auth);
741	return ret;
742    }
743}
744
745#if defined(KRB4) || defined(KRB5)
746static int
747doit (const char *hostname,
748      struct addrinfo *ai,
749      const char *remote_user,
750      const char *local_user,
751      const char *cmd,
752      size_t cmd_len,
753      int do_errsock,
754      int (*auth_func)(int s,
755		       struct sockaddr *this, struct sockaddr *that,
756		       const char *hostname, const char *remote_user,
757		       const char *local_user, size_t cmd_len,
758		       const char *cmd))
759{
760    int error;
761    struct addrinfo *a;
762    int socketfailed = 1;
763    int ret;
764
765    for (a = ai; a != NULL; a = a->ai_next) {
766	int s;
767	int errsock;
768
769	s = socket (a->ai_family, a->ai_socktype, a->ai_protocol);
770	if (s < 0)
771	    continue;
772	socketfailed = 0;
773	if (connect (s, a->ai_addr, a->ai_addrlen) < 0) {
774	    char addr[128];
775	    if(getnameinfo(a->ai_addr, a->ai_addrlen,
776			   addr, sizeof(addr), NULL, 0, NI_NUMERICHOST) == 0)
777		warn ("connect(%s [%s])", hostname, addr);
778	    else
779		warn ("connect(%s)", hostname);
780	    close (s);
781	    continue;
782	}
783	if (do_errsock) {
784	    struct addrinfo *ea, *eai;
785	    struct addrinfo hints;
786
787	    memset (&hints, 0, sizeof(hints));
788	    hints.ai_socktype = a->ai_socktype;
789	    hints.ai_protocol = a->ai_protocol;
790	    hints.ai_family   = a->ai_family;
791	    hints.ai_flags    = AI_PASSIVE;
792
793	    errsock = -1;
794
795	    error = getaddrinfo (NULL, "0", &hints, &eai);
796	    if (error)
797		errx (1, "getaddrinfo: %s", gai_strerror(error));
798	    for (ea = eai; ea != NULL; ea = ea->ai_next) {
799		errsock = socket (ea->ai_family, ea->ai_socktype,
800				  ea->ai_protocol);
801		if (errsock < 0)
802		    continue;
803		if (bind (errsock, ea->ai_addr, ea->ai_addrlen) < 0)
804		    err (1, "bind");
805		break;
806	    }
807	    if (errsock < 0)
808		err (1, "socket");
809	    freeaddrinfo (eai);
810	} else
811	    errsock = -1;
812
813	ret = proto (s, errsock,
814		     hostname,
815		     local_user, remote_user,
816		     cmd, cmd_len, auth_func);
817	close (s);
818	return ret;
819    }
820    if(socketfailed)
821	warnx ("failed to contact %s", hostname);
822    return -1;
823}
824#endif /* KRB4 || KRB5 */
825
826struct getargs args[] = {
827#ifdef KRB4
828    { "krb4",	'4', arg_flag,		&use_v4,	"Use Kerberos V4" },
829#endif
830#ifdef KRB5
831    { "krb5",	'5', arg_flag,		&use_v5,	"Use Kerberos V5" },
832    { "forward", 'f', arg_flag,		&do_forward,	"Forward credentials (krb5)"},
833    { NULL, 'G', arg_negative_flag,&do_forward,	"Don't forward credentials" },
834    { "forwardable", 'F', arg_flag,	&do_forwardable,
835      "Forward forwardable credentials" },
836#endif
837#if defined(KRB4) || defined(KRB5)
838    { "broken", 'K', arg_flag,		&use_only_broken, "Use only priv port" },
839    { "encrypt", 'x', arg_flag,		&do_encrypt,	"Encrypt connection" },
840    { NULL, 	'z', arg_negative_flag,      &do_encrypt,
841      "Don't encrypt connection", NULL },
842#endif
843#ifdef KRB5
844    { "unique", 'u', arg_flag,	&do_unique_tkfile,
845      "Use unique remote tkfile (krb5)" },
846    { "tkfile", 'U', arg_string,  &unique_tkfile,
847      "Use that remote tkfile (krb5)" },
848#endif
849    { NULL,	'd', arg_flag,		&sock_debug, "Enable socket debugging" },
850    { "input",	'n', arg_negative_flag,	&input,		"Close stdin" },
851    { "port",	'p', arg_string,	&port_str,	"Use this port",
852      "port" },
853    { "user",	'l', arg_string,	&user,		"Run as this user", "login" },
854    { "stderr", 'e', arg_negative_flag, &do_errsock,	"Don't open stderr"},
855    { "protocol", 'P', arg_string,      &protocol_version_str,
856      "Protocol version", "protocol" },
857    { "version", 0,  arg_flag,		&do_version,	NULL },
858    { "help",	 0,  arg_flag,		&do_help,	NULL }
859};
860
861static void
862usage (int ret)
863{
864    arg_printusage (args,
865		    sizeof(args) / sizeof(args[0]),
866		    NULL,
867		    "[login@]host [command]");
868    exit (ret);
869}
870
871/*
872 *
873 */
874
875int
876main(int argc, char **argv)
877{
878    int priv_port1, priv_port2;
879    int priv_socket1, priv_socket2;
880    int argindex = 0;
881    int error;
882    struct addrinfo hints, *ai;
883    int ret = 1;
884    char *cmd;
885    char *tmp;
886    size_t cmd_len;
887    const char *local_user;
888    char *host = NULL;
889    int host_index = -1;
890#ifdef KRB5
891    int status;
892#endif
893    uid_t uid;
894
895    priv_port1 = priv_port2 = IPPORT_RESERVED-1;
896    priv_socket1 = rresvport(&priv_port1);
897    priv_socket2 = rresvport(&priv_port2);
898    uid = getuid ();
899    if (setuid (uid) || (uid != 0 && setuid(0) == 0))
900	err (1, "setuid");
901
902    setprogname (argv[0]);
903
904    if (argc >= 2 && argv[1][0] != '-') {
905	host = argv[host_index = 1];
906	argindex = 1;
907    }
908
909    if (getarg (args, sizeof(args) / sizeof(args[0]), argc, argv,
910		&argindex))
911	usage (1);
912
913    if (do_help)
914	usage (0);
915
916    if (do_version) {
917	print_version (NULL);
918	return 0;
919    }
920
921    if(protocol_version_str != NULL) {
922	if(strcasecmp(protocol_version_str, "N") == 0)
923	    protocol_version = 2;
924	else if(strcasecmp(protocol_version_str, "O") == 0)
925	    protocol_version = 1;
926	else {
927	    char *end;
928	    int v;
929	    v = strtol(protocol_version_str, &end, 0);
930	    if(*end != '\0' || (v != 1 && v != 2)) {
931		errx(1, "unknown protocol version \"%s\"",
932		     protocol_version_str);
933	    }
934	    protocol_version = v;
935	}
936    }
937
938#ifdef KRB5
939    status = krb5_init_context (&context);
940    if (status) {
941	if(use_v5 == 1)
942	    errx(1, "krb5_init_context failed: %d", status);
943	else
944	    use_v5 = 0;
945    }
946
947    /* request for forwardable on the command line means we should
948       also forward */
949    if (do_forwardable == 1)
950	do_forward = 1;
951
952#endif
953
954#if defined(KRB4) && defined(KRB5)
955    if(use_v4 == -1 && use_v5 == 1)
956	use_v4 = 0;
957    if(use_v5 == -1 && use_v4 == 1)
958	use_v5 = 0;
959#endif
960
961    if (use_only_broken) {
962#ifdef KRB4
963	use_v4 = 0;
964#endif
965#ifdef KRB5
966	use_v5 = 0;
967#endif
968    }
969
970    if(priv_socket1 < 0) {
971	if (use_only_broken)
972	    errx (1, "unable to bind reserved port: is rsh setuid root?");
973	use_broken = 0;
974    }
975
976#if defined(KRB4) || defined(KRB5)
977    if (do_encrypt == 1 && use_only_broken)
978	errx (1, "encryption not supported with old style authentication");
979#endif
980
981
982
983#ifdef KRB5
984    if (do_unique_tkfile && unique_tkfile != NULL)
985	errx (1, "Only one of -u and -U allowed.");
986
987    if (do_unique_tkfile)
988	strcpy(tkfile,"-u ");
989    else if (unique_tkfile != NULL) {
990	if (strchr(unique_tkfile,' ') != NULL) {
991	    warnx("Space is not allowed in tkfilename");
992	    usage(1);
993	}
994	do_unique_tkfile = 1;
995	snprintf (tkfile, sizeof(tkfile), "-U %s ", unique_tkfile);
996    }
997#endif
998
999    if (host == NULL) {
1000	if (argc - argindex < 1)
1001	    usage (1);
1002	else
1003	    host = argv[host_index = argindex++];
1004    }
1005
1006    if((tmp = strchr(host, '@')) != NULL) {
1007	*tmp++ = '\0';
1008	user = host;
1009	host = tmp;
1010    }
1011
1012    if (argindex == argc) {
1013	close (priv_socket1);
1014	close (priv_socket2);
1015	argv[0] = "rlogin";
1016	execvp ("rlogin", argv);
1017	err (1, "execvp rlogin");
1018    }
1019
1020    local_user = get_default_username ();
1021    if (local_user == NULL)
1022	errx (1, "who are you?");
1023
1024    if (user == NULL)
1025	user = local_user;
1026
1027    cmd_len = construct_command(&cmd, argc - argindex, argv + argindex);
1028
1029    /*
1030     * Try all different authentication methods
1031     */
1032
1033#ifdef KRB5
1034    if (ret && use_v5) {
1035	memset (&hints, 0, sizeof(hints));
1036	hints.ai_socktype = SOCK_STREAM;
1037	hints.ai_protocol = IPPROTO_TCP;
1038
1039	if(port_str == NULL) {
1040	    error = getaddrinfo(host, "kshell", &hints, &ai);
1041	    if(error == EAI_NONAME)
1042		error = getaddrinfo(host, "544", &hints, &ai);
1043	} else
1044	    error = getaddrinfo(host, port_str, &hints, &ai);
1045
1046	if(error)
1047	    errx (1, "getaddrinfo: %s", gai_strerror(error));
1048
1049	auth_method = AUTH_KRB5;
1050      again:
1051	ret = doit (host, ai, user, local_user, cmd, cmd_len,
1052		    do_errsock,
1053		    send_krb5_auth);
1054	if(ret != 0 && sendauth_version_error &&
1055	   protocol_version == 2) {
1056	    protocol_version = 1;
1057	    goto again;
1058	}
1059	freeaddrinfo(ai);
1060    }
1061#endif
1062#ifdef KRB4
1063    if (ret && use_v4) {
1064	memset (&hints, 0, sizeof(hints));
1065	hints.ai_socktype = SOCK_STREAM;
1066	hints.ai_protocol = IPPROTO_TCP;
1067
1068	if(port_str == NULL) {
1069	    if(do_encrypt) {
1070		error = getaddrinfo(host, "ekshell", &hints, &ai);
1071		if(error == EAI_NONAME)
1072		    error = getaddrinfo(host, "545", &hints, &ai);
1073	    } else {
1074		error = getaddrinfo(host, "kshell", &hints, &ai);
1075		if(error == EAI_NONAME)
1076		    error = getaddrinfo(host, "544", &hints, &ai);
1077	    }
1078	} else
1079	    error = getaddrinfo(host, port_str, &hints, &ai);
1080
1081	if(error)
1082	    errx (1, "getaddrinfo: %s", gai_strerror(error));
1083	auth_method = AUTH_KRB4;
1084	ret = doit (host, ai, user, local_user, cmd, cmd_len,
1085		    do_errsock,
1086		    send_krb4_auth);
1087	freeaddrinfo(ai);
1088    }
1089#endif
1090    if (ret && use_broken) {
1091	memset (&hints, 0, sizeof(hints));
1092	hints.ai_socktype = SOCK_STREAM;
1093	hints.ai_protocol = IPPROTO_TCP;
1094
1095	if(port_str == NULL) {
1096	    error = getaddrinfo(host, "shell", &hints, &ai);
1097	    if(error == EAI_NONAME)
1098		error = getaddrinfo(host, "514", &hints, &ai);
1099	} else
1100	    error = getaddrinfo(host, port_str, &hints, &ai);
1101
1102	if(error)
1103	    errx (1, "getaddrinfo: %s", gai_strerror(error));
1104
1105	auth_method = AUTH_BROKEN;
1106	ret = doit_broken (argc, argv, host_index, ai,
1107			   user, local_user,
1108			   priv_socket1,
1109			   do_errsock ? priv_socket2 : -1,
1110			   cmd, cmd_len);
1111	freeaddrinfo(ai);
1112    }
1113    free(cmd);
1114    return ret;
1115}
1116