xref: /dragonfly/lib/libcompat/4.3/rexec.c (revision bcb3e04d)
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, const char **aname, const 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 == NULL) {
193 					char *tmp;
194 					tmp = malloc(strlen(tokval) + 1);
195 					strcpy(tmp, tokval);
196 					*aname = tmp;
197 				} else {
198 					if (strcmp(*aname, tokval))
199 						goto next;
200 				}
201 			break;
202 		case PASSWD:
203 			if ((*aname == 0 || strcmp(*aname, "anonymous")) &&
204 			    fstat(fileno(cfile), &stb) >= 0 &&
205 			    (stb.st_mode & 077) != 0) {
206 	warnx("Error: .netrc file is readable by others.");
207 	warnx("Remove password or make file unreadable by others.");
208 				goto bad;
209 			}
210 			if (token() && *apass == 0) {
211 				char *tmp;
212 				tmp = malloc(strlen(tokval) + 1);
213 				strcpy(tmp, tokval);
214 				*apass = tmp;
215 			}
216 			break;
217 		case ACCOUNT:
218 			if (fstat(fileno(cfile), &stb) >= 0
219 			    && (stb.st_mode & 077) != 0) {
220 	warnx("Error: .netrc file is readable by others.");
221 	warnx("Remove account or make file unreadable by others.");
222 				goto bad;
223 			}
224 			if (token() && *aacct == 0) {
225 				*aacct = malloc((unsigned) strlen(tokval) + 1);
226 				(void) strcpy(*aacct, tokval);
227 			}
228 			break;
229 		case MACDEF:
230 			while ((c=getc(cfile)) != EOF &&
231 						(c == ' ' || c == '\t'))
232 				;
233 			if (c == EOF || c == '\n') {
234 				printf("Missing macdef name argument.\n");
235 				goto bad;
236 			}
237 			if (macnum == 16) {
238 				printf("Limit of 16 macros have already been defined\n");
239 				goto bad;
240 			}
241 			tmp = macros[macnum].mac_name;
242 			*tmp++ = c;
243 			for (i=0; i < 8 && (c=getc(cfile)) != EOF &&
244 			    !isspace(c); ++i) {
245 				*tmp++ = c;
246 			}
247 			if (c == EOF) {
248 				printf("Macro definition missing null line terminator.\n");
249 				goto bad;
250 			}
251 			*tmp = '\0';
252 			if (c != '\n') {
253 				while ((c=getc(cfile)) != EOF && c != '\n');
254 			}
255 			if (c == EOF) {
256 				printf("Macro definition missing null line terminator.\n");
257 				goto bad;
258 			}
259 			if (macnum == 0) {
260 				macros[macnum].mac_start = macbuf;
261 			}
262 			else {
263 				macros[macnum].mac_start = macros[macnum-1].mac_end + 1;
264 			}
265 			tmp = macros[macnum].mac_start;
266 			while (tmp != macbuf + 4096) {
267 				if ((c=getc(cfile)) == EOF) {
268 				printf("Macro definition missing null line terminator.\n");
269 					goto bad;
270 				}
271 				*tmp = c;
272 				if (*tmp == '\n') {
273 					if (*(tmp-1) == '\0') {
274 					   macros[macnum++].mac_end = tmp - 1;
275 					   break;
276 					}
277 					*tmp = '\0';
278 				}
279 				tmp++;
280 			}
281 			if (tmp == macbuf + 4096) {
282 				printf("4K macro buffer exceeded\n");
283 				goto bad;
284 			}
285 			break;
286 		default:
287 			warnx("Unknown .netrc keyword %s", tokval);
288 			break;
289 		}
290 		goto done;
291 	}
292 done:
293 	(void) fclose(cfile);
294 	return (0);
295 bad:
296 	(void) fclose(cfile);
297 	return (-1);
298 }
299 
300 int
301 rexec_af(char **ahost, int rport, const char *name, const char *pass,
302     const char *cmd, int *fd2p, sa_family_t *af)
303 {
304 	struct sockaddr_storage sa2, from;
305 	struct addrinfo hints, *res0;
306 	const char *orig_name = name;
307 	const char *orig_pass = pass;
308 	static char *ahostbuf;
309 	u_short port = 0;
310 	int s, timo = 1, s3;
311 	char c;
312 	int gai;
313 	char servbuff[NI_MAXSERV];
314 
315 	snprintf(servbuff, sizeof(servbuff), "%d", ntohs(rport));
316 	servbuff[sizeof(servbuff) - 1] = '\0';
317 
318 	memset(&hints, '\0', sizeof(hints));
319 	if (af)
320 		hints.ai_family = *af;
321 	hints.ai_socktype = SOCK_STREAM;
322 	hints.ai_flags = AI_CANONNAME;
323 	gai = getaddrinfo(*ahost, servbuff, &hints, &res0);
324 	if (gai){
325 		/* XXX: set errno? */
326 		return -1;
327 	}
328 
329 	if (res0->ai_canonname){
330 		free (ahostbuf);
331 		ahostbuf = strdup (res0->ai_canonname);
332 		if (ahostbuf == NULL) {
333 			perror ("rexec: strdup");
334 			return (-1);
335 		}
336 		*ahost = ahostbuf;
337 	} else {
338 		*ahost = NULL;
339 		__set_errno (ENOENT);
340 		return -1;
341 	}
342 	ruserpass(res0->ai_canonname, &name, &pass, 0);
343 retry:
344 	s = socket(res0->ai_family, res0->ai_socktype, 0);
345 	if (s < 0) {
346 		perror("rexec: socket");
347 		return (-1);
348 	}
349 	if (connect(s, res0->ai_addr, res0->ai_addrlen) < 0) {
350 		if (errno == ECONNREFUSED && timo <= 16) {
351 			(void) close(s);
352 			sleep(timo);
353 			timo *= 2;
354 			goto retry;
355 		}
356 		perror(res0->ai_canonname);
357 		return (-1);
358 	}
359 	if (fd2p == 0) {
360 		(void) write(s, "", 1);
361 		port = 0;
362 	} else {
363 		char num[32];
364 		int s2;
365 		socklen_t sa2len;
366 
367 		s2 = socket(res0->ai_family, res0->ai_socktype, 0);
368 		if (s2 < 0) {
369 			(void) close(s);
370 			return (-1);
371 		}
372 		listen(s2, 1);
373 		sa2len = sizeof (sa2);
374 		if (getsockname(s2, (struct sockaddr *)&sa2, &sa2len) < 0) {
375 			perror("getsockname");
376 			(void) close(s2);
377 			goto bad;
378 		} else if (sa2len != SA_LEN((struct sockaddr *)&sa2)) {
379 			__set_errno(EINVAL);
380 			(void) close(s2);
381 			goto bad;
382 		}
383 		port = 0;
384 		if (!getnameinfo((struct sockaddr *)&sa2, sa2len,
385 				 NULL, 0, servbuff, sizeof(servbuff),
386 				 NI_NUMERICSERV))
387 			port = atoi(servbuff);
388 		(void) sprintf(num, "%u", port);
389 		(void) write(s, num, strlen(num)+1);
390 		{ socklen_t len = sizeof (from);
391 		  s3 = accept(s2, (struct sockaddr *)&from,
392 						  &len);
393 		  close(s2);
394 		  if (s3 < 0) {
395 			perror("accept");
396 			port = 0;
397 			goto bad;
398 		  }
399 		}
400 		*fd2p = s3;
401 	}
402 
403 	(void) write(s, name, strlen(name) + 1);
404 	/* should public key encypt the password here */
405 	(void) write(s, pass, strlen(pass) + 1);
406 	(void) write(s, cmd, strlen(cmd) + 1);
407 
408 	/* We don't need the memory allocated for the name and the password
409 	   in ruserpass anymore.  */
410 	if (name != orig_name)
411 	  free ((char *) name);
412 	if (pass != orig_pass)
413 	  free ((char *) pass);
414 
415 	if (read(s, &c, 1) != 1) {
416 		perror(*ahost);
417 		goto bad;
418 	}
419 	if (c != 0) {
420 		while (read(s, &c, 1) == 1) {
421 			(void) write(2, &c, 1);
422 			if (c == '\n')
423 				break;
424 		}
425 		goto bad;
426 	}
427 	freeaddrinfo(res0);
428 	return (s);
429 bad:
430 	if (port)
431 		(void) close(*fd2p);
432 	(void) close(s);
433 	freeaddrinfo(res0);
434 	return (-1);
435 }
436 
437 
438 int
439 rexec(char **ahost, int rport, const char *name, const char *pass, char *cmd, int *fd2p)
440 {
441 	struct sockaddr_in sin, sin2, from;
442 	struct hostent *hp;
443 	u_short port;
444 	int s, timo = 1, s3;
445 	char c;
446 	char *acct = NULL;
447 
448 	hp = gethostbyname(*ahost);
449 	if (hp == 0) {
450 		herror(*ahost);
451 		return (-1);
452 	}
453 	*ahost = hp->h_name;
454 	ruserpass(hp->h_name, &name, &pass, &acct);
455 	if (acct != NULL)
456 		free(acct);
457 retry:
458 	s = socket(AF_INET, SOCK_STREAM, 0);
459 	if (s < 0) {
460 		perror("rexec: socket");
461 		return (-1);
462 	}
463 	sin.sin_family = hp->h_addrtype;
464 	sin.sin_port = rport;
465 	bcopy(hp->h_addr, (caddr_t)&sin.sin_addr, hp->h_length);
466 	if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
467 		if (errno == ECONNREFUSED && timo <= 16) {
468 			(void) close(s);
469 			sleep(timo);
470 			timo *= 2;
471 			goto retry;
472 		}
473 		perror(hp->h_name);
474 		return (-1);
475 	}
476 	if (fd2p == 0) {
477 		(void) write(s, "", 1);
478 		port = 0;
479 	} else {
480 		char num[8];
481 		int s2, sin2len;
482 
483 		s2 = socket(AF_INET, SOCK_STREAM, 0);
484 		if (s2 < 0) {
485 			(void) close(s);
486 			return (-1);
487 		}
488 		listen(s2, 1);
489 		sin2len = sizeof (sin2);
490 		if (getsockname(s2, (struct sockaddr *)&sin2, &sin2len) < 0 ||
491 		  sin2len != sizeof (sin2)) {
492 			perror("getsockname");
493 			(void) close(s2);
494 			goto bad;
495 		}
496 		port = ntohs((u_short)sin2.sin_port);
497 		(void) sprintf(num, "%u", port);
498 		(void) write(s, num, strlen(num)+1);
499 		{ int len = sizeof (from);
500 		  s3 = accept(s2, (struct sockaddr *)&from, &len);
501 		  close(s2);
502 		  if (s3 < 0) {
503 			perror("accept");
504 			port = 0;
505 			goto bad;
506 		  }
507 		}
508 		*fd2p = s3;
509 	}
510 	(void) write(s, name, strlen(name) + 1);
511 	/* should public key encypt the password here */
512 	(void) write(s, pass, strlen(pass) + 1);
513 	(void) write(s, cmd, strlen(cmd) + 1);
514 	if (read(s, &c, 1) != 1) {
515 		perror(*ahost);
516 		goto bad;
517 	}
518 	if (c != 0) {
519 		while (read(s, &c, 1) == 1) {
520 			(void) write(2, &c, 1);
521 			if (c == '\n')
522 				break;
523 		}
524 		goto bad;
525 	}
526 	return (s);
527 bad:
528 	if (port)
529 		(void) close(*fd2p);
530 	(void) close(s);
531 	return (-1);
532 }
533