xref: /dragonfly/lib/libcompat/4.3/rexec.c (revision 2038fb68)
1 /*
2  * Copyright (c) 1980, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
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.
20  *
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
31  * SUCH DAMAGE.
32  *
33  * $FreeBSD: src/lib/libcompat/4.3/rexec.c,v 1.5.8.3 2000/11/22 13:36:00 ben Exp $
34  * $DragonFly: src/lib/libcompat/4.3/rexec.c,v 1.6 2008/10/05 18:26:41 swildner Exp $
35  *
36  * @(#)rexec.c	8.1 (Berkeley) 6/4/93
37  */
38 
39 #include <sys/types.h>
40 #include <sys/uio.h>
41 #include <sys/socket.h>
42 #include <sys/param.h>
43 #include <sys/stat.h>
44 
45 #include <netinet/in.h>
46 
47 #include <stdio.h>
48 #include <unistd.h>
49 #include <string.h>
50 #include <netdb.h>
51 #include <errno.h>
52 #include <ctype.h>
53 #include <err.h>
54 #include <stdlib.h>
55 #include <unistd.h>
56 
57 int	rexecoptions;
58 char	*getpass(), *getlogin();
59 
60 /*
61  * Options and other state info.
62  */
63 struct macel {
64 	char mac_name[9];	/* macro name */
65 	char *mac_start;	/* start of macro in macbuf */
66 	char *mac_end;		/* end of macro in macbuf */
67 };
68 
69 int macnum;			/* number of defined macros */
70 struct macel macros[16];
71 char macbuf[4096];
72 
73 static	FILE *cfile;
74 
75 #define	DEFAULT	1
76 #define	LOGIN	2
77 #define	PASSWD	3
78 #define	ACCOUNT 4
79 #define MACDEF  5
80 #define	ID	10
81 #define	MACH	11
82 
83 static char tokval[100];
84 
85 static struct toktab {
86 	char *tokstr;
87 	int tval;
88 } toktab[]= {
89 	{ "default",	DEFAULT },
90 	{ "login",	LOGIN },
91 	{ "password",	PASSWD },
92 	{ "passwd",	PASSWD },
93 	{ "account",	ACCOUNT },
94 	{ "machine",	MACH },
95 	{ "macdef",	MACDEF },
96 	{ NULL,		0 }
97 };
98 
99 static int
100 token(void)
101 {
102 	char *cp;
103 	int c;
104 	struct toktab *t;
105 
106 	if (feof(cfile) || ferror(cfile))
107 		return (0);
108 	while ((c = getc(cfile)) != EOF &&
109 	    (c == '\n' || c == '\t' || c == ' ' || c == ','))
110 		continue;
111 	if (c == EOF)
112 		return (0);
113 	cp = tokval;
114 	if (c == '"') {
115 		while ((c = getc(cfile)) != EOF && c != '"') {
116 			if (c == '\\')
117 				c = getc(cfile);
118 			*cp++ = c;
119 		}
120 	} else {
121 		*cp++ = c;
122 		while ((c = getc(cfile)) != EOF
123 		    && c != '\n' && c != '\t' && c != ' ' && c != ',') {
124 			if (c == '\\')
125 				c = getc(cfile);
126 			*cp++ = c;
127 		}
128 	}
129 	*cp = 0;
130 	if (tokval[0] == 0)
131 		return (0);
132 	for (t = toktab; t->tokstr; t++)
133 		if (!strcmp(t->tokstr, tokval))
134 			return (t->tval);
135 	return (ID);
136 }
137 
138 static int
139 ruserpass(char *host, char **aname, char **apass, char **aacct)
140 {
141 	char *hdir, buf[BUFSIZ], *tmp;
142 	char myname[MAXHOSTNAMELEN], *mydomain;
143 	int t, i, c, usedefault = 0;
144 	struct stat stb;
145 
146 	hdir = getenv("HOME");
147 	if (hdir == NULL)
148 		hdir = ".";
149 	if (strlen(hdir) + 8 > sizeof(buf))
150 		return (0);
151 	(void) sprintf(buf, "%s/.netrc", hdir);
152 	cfile = fopen(buf, "r");
153 	if (cfile == NULL) {
154 		if (errno != ENOENT)
155 			warn("%s", buf);
156 		return (0);
157 	}
158 	if (gethostname(myname, sizeof(myname)) < 0)
159 		myname[0] = '\0';
160 	if ((mydomain = strchr(myname, '.')) == NULL)
161 		mydomain = "";
162 next:
163 	while ((t = token())) switch(t) {
164 
165 	case DEFAULT:
166 		usedefault = 1;
167 		/* FALL THROUGH */
168 
169 	case MACH:
170 		if (!usedefault) {
171 			if (token() != ID)
172 				continue;
173 			/*
174 			 * Allow match either for user's input host name
175 			 * or official hostname.  Also allow match of
176 			 * incompletely-specified host in local domain.
177 			 */
178 			if (strcasecmp(host, tokval) == 0)
179 				goto match;
180 			if ((tmp = strchr(host, '.')) != NULL &&
181 			    strcasecmp(tmp, mydomain) == 0 &&
182 			    strncasecmp(host, tokval, tmp - host) == 0 &&
183 			    tokval[tmp - host] == '\0')
184 				goto match;
185 			continue;
186 		}
187 	match:
188 		while ((t = token()) && t != MACH && t != DEFAULT) switch(t) {
189 
190 		case LOGIN:
191 			if (token())
192 				if (*aname == 0) {
193 					*aname = malloc((unsigned) strlen(tokval) + 1);
194 					(void) strcpy(*aname, tokval);
195 				} else {
196 					if (strcmp(*aname, tokval))
197 						goto next;
198 				}
199 			break;
200 		case PASSWD:
201 			if ((*aname == 0 || strcmp(*aname, "anonymous")) &&
202 			    fstat(fileno(cfile), &stb) >= 0 &&
203 			    (stb.st_mode & 077) != 0) {
204 	warnx("Error: .netrc file is readable by others.");
205 	warnx("Remove password or make file unreadable by others.");
206 				goto bad;
207 			}
208 			if (token() && *apass == 0) {
209 				*apass = malloc((unsigned) strlen(tokval) + 1);
210 				(void) strcpy(*apass, tokval);
211 			}
212 			break;
213 		case ACCOUNT:
214 			if (fstat(fileno(cfile), &stb) >= 0
215 			    && (stb.st_mode & 077) != 0) {
216 	warnx("Error: .netrc file is readable by others.");
217 	warnx("Remove account or make file unreadable by others.");
218 				goto bad;
219 			}
220 			if (token() && *aacct == 0) {
221 				*aacct = malloc((unsigned) strlen(tokval) + 1);
222 				(void) strcpy(*aacct, tokval);
223 			}
224 			break;
225 		case MACDEF:
226 			while ((c=getc(cfile)) != EOF &&
227 						(c == ' ' || c == '\t'))
228 				;
229 			if (c == EOF || c == '\n') {
230 				printf("Missing macdef name argument.\n");
231 				goto bad;
232 			}
233 			if (macnum == 16) {
234 				printf("Limit of 16 macros have already been defined\n");
235 				goto bad;
236 			}
237 			tmp = macros[macnum].mac_name;
238 			*tmp++ = c;
239 			for (i=0; i < 8 && (c=getc(cfile)) != EOF &&
240 			    !isspace(c); ++i) {
241 				*tmp++ = c;
242 			}
243 			if (c == EOF) {
244 				printf("Macro definition missing null line terminator.\n");
245 				goto bad;
246 			}
247 			*tmp = '\0';
248 			if (c != '\n') {
249 				while ((c=getc(cfile)) != EOF && c != '\n');
250 			}
251 			if (c == EOF) {
252 				printf("Macro definition missing null line terminator.\n");
253 				goto bad;
254 			}
255 			if (macnum == 0) {
256 				macros[macnum].mac_start = macbuf;
257 			}
258 			else {
259 				macros[macnum].mac_start = macros[macnum-1].mac_end + 1;
260 			}
261 			tmp = macros[macnum].mac_start;
262 			while (tmp != macbuf + 4096) {
263 				if ((c=getc(cfile)) == EOF) {
264 				printf("Macro definition missing null line terminator.\n");
265 					goto bad;
266 				}
267 				*tmp = c;
268 				if (*tmp == '\n') {
269 					if (*(tmp-1) == '\0') {
270 					   macros[macnum++].mac_end = tmp - 1;
271 					   break;
272 					}
273 					*tmp = '\0';
274 				}
275 				tmp++;
276 			}
277 			if (tmp == macbuf + 4096) {
278 				printf("4K macro buffer exceeded\n");
279 				goto bad;
280 			}
281 			break;
282 		default:
283 			warnx("Unknown .netrc keyword %s", tokval);
284 			break;
285 		}
286 		goto done;
287 	}
288 done:
289 	(void) fclose(cfile);
290 	return (0);
291 bad:
292 	(void) fclose(cfile);
293 	return (-1);
294 }
295 
296 int
297 rexec_af(char **ahost, int rport, const char *name, const char *pass,
298     const char *cmd, int *fd2p, sa_family_t *af)
299 {
300 	struct sockaddr_storage sa2, from;
301 	struct addrinfo hints, *res0;
302 	const char *orig_name = name;
303 	const char *orig_pass = pass;
304 	static char *ahostbuf;
305 	u_short port = 0;
306 	int s, timo = 1, s3;
307 	char c;
308 	int gai;
309 	char servbuff[NI_MAXSERV];
310 
311 	snprintf(servbuff, sizeof(servbuff), "%d", ntohs(rport));
312 	servbuff[sizeof(servbuff) - 1] = '\0';
313 
314 	memset(&hints, '\0', sizeof(hints));
315 	hints.ai_family = af;
316 	hints.ai_socktype = SOCK_STREAM;
317 	hints.ai_flags = AI_CANONNAME;
318 	gai = getaddrinfo(*ahost, servbuff, &hints, &res0);
319 	if (gai){
320 		/* XXX: set errno? */
321 		return -1;
322 	}
323 
324 	if (res0->ai_canonname){
325 		free (ahostbuf);
326 		ahostbuf = strdup (res0->ai_canonname);
327 		if (ahostbuf == NULL) {
328 			perror ("rexec: strdup");
329 			return (-1);
330 		}
331 		*ahost = ahostbuf;
332 	} else {
333 		*ahost = NULL;
334 		__set_errno (ENOENT);
335 		return -1;
336 	}
337 	ruserpass(res0->ai_canonname, &name, &pass, 0);
338 retry:
339 	s = socket(res0->ai_family, res0->ai_socktype, 0);
340 	if (s < 0) {
341 		perror("rexec: socket");
342 		return (-1);
343 	}
344 	if (connect(s, res0->ai_addr, res0->ai_addrlen) < 0) {
345 		if (errno == ECONNREFUSED && timo <= 16) {
346 			(void) close(s);
347 			sleep(timo);
348 			timo *= 2;
349 			goto retry;
350 		}
351 		perror(res0->ai_canonname);
352 		return (-1);
353 	}
354 	if (fd2p == 0) {
355 		(void) write(s, "", 1);
356 		port = 0;
357 	} else {
358 		char num[32];
359 		int s2;
360 		socklen_t sa2len;
361 
362 		s2 = socket(res0->ai_family, res0->ai_socktype, 0);
363 		if (s2 < 0) {
364 			(void) close(s);
365 			return (-1);
366 		}
367 		listen(s2, 1);
368 		sa2len = sizeof (sa2);
369 		if (getsockname(s2, (struct sockaddr *)&sa2, &sa2len) < 0) {
370 			perror("getsockname");
371 			(void) close(s2);
372 			goto bad;
373 		} else if (sa2len != SA_LEN((struct sockaddr *)&sa2)) {
374 			__set_errno(EINVAL);
375 			(void) close(s2);
376 			goto bad;
377 		}
378 		port = 0;
379 		if (!getnameinfo((struct sockaddr *)&sa2, sa2len,
380 				 NULL, 0, servbuff, sizeof(servbuff),
381 				 NI_NUMERICSERV))
382 			port = atoi(servbuff);
383 		(void) sprintf(num, "%u", port);
384 		(void) write(s, num, strlen(num)+1);
385 		{ socklen_t len = sizeof (from);
386 		  s3 = accept(s2, (struct sockaddr *)&from,
387 						  &len);
388 		  close(s2);
389 		  if (s3 < 0) {
390 			perror("accept");
391 			port = 0;
392 			goto bad;
393 		  }
394 		}
395 		*fd2p = s3;
396 	}
397 
398 	(void) write(s, name, strlen(name) + 1);
399 	/* should public key encypt the password here */
400 	(void) write(s, pass, strlen(pass) + 1);
401 	(void) write(s, cmd, strlen(cmd) + 1);
402 
403 	/* We don't need the memory allocated for the name and the password
404 	   in ruserpass anymore.  */
405 	if (name != orig_name)
406 	  free ((char *) name);
407 	if (pass != orig_pass)
408 	  free ((char *) pass);
409 
410 	if (read(s, &c, 1) != 1) {
411 		perror(*ahost);
412 		goto bad;
413 	}
414 	if (c != 0) {
415 		while (read(s, &c, 1) == 1) {
416 			(void) write(2, &c, 1);
417 			if (c == '\n')
418 				break;
419 		}
420 		goto bad;
421 	}
422 	freeaddrinfo(res0);
423 	return (s);
424 bad:
425 	if (port)
426 		(void) close(*fd2p);
427 	(void) close(s);
428 	freeaddrinfo(res0);
429 	return (-1);
430 }
431 
432 
433 int
434 rexec(char **ahost, int rport, char *name, char *pass, char *cmd, int *fd2p)
435 {
436 	struct sockaddr_in sin, sin2, from;
437 	struct hostent *hp;
438 	u_short port;
439 	int s, timo = 1, s3;
440 	char c;
441 	char *acct = NULL;
442 
443 	hp = gethostbyname(*ahost);
444 	if (hp == 0) {
445 		herror(*ahost);
446 		return (-1);
447 	}
448 	*ahost = hp->h_name;
449 	ruserpass(hp->h_name, &name, &pass, &acct);
450 	if (acct != NULL)
451 		free(acct);
452 retry:
453 	s = socket(AF_INET, SOCK_STREAM, 0);
454 	if (s < 0) {
455 		perror("rexec: socket");
456 		return (-1);
457 	}
458 	sin.sin_family = hp->h_addrtype;
459 	sin.sin_port = rport;
460 	bcopy(hp->h_addr, (caddr_t)&sin.sin_addr, hp->h_length);
461 	if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
462 		if (errno == ECONNREFUSED && timo <= 16) {
463 			(void) close(s);
464 			sleep(timo);
465 			timo *= 2;
466 			goto retry;
467 		}
468 		perror(hp->h_name);
469 		return (-1);
470 	}
471 	if (fd2p == 0) {
472 		(void) write(s, "", 1);
473 		port = 0;
474 	} else {
475 		char num[8];
476 		int s2, sin2len;
477 
478 		s2 = socket(AF_INET, SOCK_STREAM, 0);
479 		if (s2 < 0) {
480 			(void) close(s);
481 			return (-1);
482 		}
483 		listen(s2, 1);
484 		sin2len = sizeof (sin2);
485 		if (getsockname(s2, (struct sockaddr *)&sin2, &sin2len) < 0 ||
486 		  sin2len != sizeof (sin2)) {
487 			perror("getsockname");
488 			(void) close(s2);
489 			goto bad;
490 		}
491 		port = ntohs((u_short)sin2.sin_port);
492 		(void) sprintf(num, "%u", port);
493 		(void) write(s, num, strlen(num)+1);
494 		{ int len = sizeof (from);
495 		  s3 = accept(s2, (struct sockaddr *)&from, &len);
496 		  close(s2);
497 		  if (s3 < 0) {
498 			perror("accept");
499 			port = 0;
500 			goto bad;
501 		  }
502 		}
503 		*fd2p = s3;
504 	}
505 	(void) write(s, name, strlen(name) + 1);
506 	/* should public key encypt the password here */
507 	(void) write(s, pass, strlen(pass) + 1);
508 	(void) write(s, cmd, strlen(cmd) + 1);
509 	if (read(s, &c, 1) != 1) {
510 		perror(*ahost);
511 		goto bad;
512 	}
513 	if (c != 0) {
514 		while (read(s, &c, 1) == 1) {
515 			(void) write(2, &c, 1);
516 			if (c == '\n')
517 				break;
518 		}
519 		goto bad;
520 	}
521 	return (s);
522 bad:
523 	if (port)
524 		(void) close(*fd2p);
525 	(void) close(s);
526 	return (-1);
527 }
528