xref: /dragonfly/lib/libcompat/4.3/rexec.c (revision 110def69)
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. 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.
16  *
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
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD: src/lib/libcompat/4.3/rexec.c,v 1.5.8.3 2000/11/22 13:36:00 ben Exp $
30  *
31  * @(#)rexec.c	8.1 (Berkeley) 6/4/93
32  */
33 
34 #include <sys/types.h>
35 #include <sys/uio.h>
36 #include <sys/socket.h>
37 #include <sys/param.h>
38 #include <sys/stat.h>
39 
40 #include <netinet/in.h>
41 
42 #include <stdio.h>
43 #include <unistd.h>
44 #include <string.h>
45 #include <netdb.h>
46 #include <errno.h>
47 #include <ctype.h>
48 #include <err.h>
49 #include <stdlib.h>
50 
51 #define	SA_LEN(addr)		((addr)->sa_len)
52 #define	__set_errno(val)	errno = (val)
53 
54 int	rexecoptions;
55 char	*getpass(), *getlogin();
56 
57 /*
58  * Options and other state info.
59  */
60 struct macel {
61 	char mac_name[9];	/* macro name */
62 	char *mac_start;	/* start of macro in macbuf */
63 	char *mac_end;		/* end of macro in macbuf */
64 };
65 
66 int macnum;			/* number of defined macros */
67 struct macel macros[16];
68 char macbuf[4096];
69 
70 static	FILE *cfile;
71 
72 #define	DEFAULT	1
73 #define	LOGIN	2
74 #define	PASSWD	3
75 #define	ACCOUNT 4
76 #define MACDEF  5
77 #define	ID	10
78 #define	MACH	11
79 
80 static char tokval[100];
81 
82 static struct toktab {
83 	char *tokstr;
84 	int tval;
85 } toktab[]= {
86 	{ "default",	DEFAULT },
87 	{ "login",	LOGIN },
88 	{ "password",	PASSWD },
89 	{ "passwd",	PASSWD },
90 	{ "account",	ACCOUNT },
91 	{ "machine",	MACH },
92 	{ "macdef",	MACDEF },
93 	{ NULL,		0 }
94 };
95 
96 static int
97 token(void)
98 {
99 	char *cp;
100 	int c;
101 	struct toktab *t;
102 
103 	if (feof(cfile) || ferror(cfile))
104 		return (0);
105 	while ((c = getc(cfile)) != EOF &&
106 	    (c == '\n' || c == '\t' || c == ' ' || c == ','))
107 		continue;
108 	if (c == EOF)
109 		return (0);
110 	cp = tokval;
111 	if (c == '"') {
112 		while ((c = getc(cfile)) != EOF && c != '"') {
113 			if (c == '\\')
114 				c = getc(cfile);
115 			*cp++ = c;
116 		}
117 	} else {
118 		*cp++ = c;
119 		while ((c = getc(cfile)) != EOF
120 		    && c != '\n' && c != '\t' && c != ' ' && c != ',') {
121 			if (c == '\\')
122 				c = getc(cfile);
123 			*cp++ = c;
124 		}
125 	}
126 	*cp = 0;
127 	if (tokval[0] == 0)
128 		return (0);
129 	for (t = toktab; t->tokstr; t++)
130 		if (!strcmp(t->tokstr, tokval))
131 			return (t->tval);
132 	return (ID);
133 }
134 
135 static int
136 ruserpass(char *host, const char **aname, const char **apass, char **aacct)
137 {
138 	char *hdir, buf[BUFSIZ], *tmp;
139 	char myname[MAXHOSTNAMELEN], *mydomain;
140 	int t, i, c, usedefault = 0;
141 	struct stat stb;
142 
143 	hdir = getenv("HOME");
144 	if (hdir == NULL)
145 		hdir = ".";
146 	if (strlen(hdir) + 8 > sizeof(buf))
147 		return (0);
148 	(void) sprintf(buf, "%s/.netrc", hdir);
149 	cfile = fopen(buf, "r");
150 	if (cfile == NULL) {
151 		if (errno != ENOENT)
152 			warn("%s", buf);
153 		return (0);
154 	}
155 	if (gethostname(myname, sizeof(myname)) < 0)
156 		myname[0] = '\0';
157 	if ((mydomain = strchr(myname, '.')) == NULL)
158 		mydomain = "";
159 next:
160 	while ((t = token())) switch(t) {
161 
162 	case DEFAULT:
163 		usedefault = 1;
164 		/* FALL THROUGH */
165 
166 	case MACH:
167 		if (!usedefault) {
168 			if (token() != ID)
169 				continue;
170 			/*
171 			 * Allow match either for user's input host name
172 			 * or official hostname.  Also allow match of
173 			 * incompletely-specified host in local domain.
174 			 */
175 			if (strcasecmp(host, tokval) == 0)
176 				goto match;
177 			if ((tmp = strchr(host, '.')) != NULL &&
178 			    strcasecmp(tmp, mydomain) == 0 &&
179 			    strncasecmp(host, tokval, tmp - host) == 0 &&
180 			    tokval[tmp - host] == '\0')
181 				goto match;
182 			continue;
183 		}
184 	match:
185 		while ((t = token()) && t != MACH && t != DEFAULT) switch(t) {
186 
187 		case LOGIN:
188 			if (token()) {
189 				if (*aname == NULL) {
190 					char *tmp;
191 					tmp = malloc(strlen(tokval) + 1);
192 					strcpy(tmp, tokval);
193 					*aname = tmp;
194 				} else {
195 					if (strcmp(*aname, tokval))
196 						goto next;
197 				}
198 			}
199 			break;
200 		case PASSWD:
201 			if ((*aname == NULL || 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 == NULL) {
209 				char *tmp;
210 				tmp = malloc(strlen(tokval) + 1);
211 				strcpy(tmp, tokval);
212 				*apass = tmp;
213 			}
214 			break;
215 		case ACCOUNT:
216 			if (fstat(fileno(cfile), &stb) >= 0
217 			    && (stb.st_mode & 077) != 0) {
218 	warnx("Error: .netrc file is readable by others.");
219 	warnx("Remove account or make file unreadable by others.");
220 				goto bad;
221 			}
222 			if (token() && *aacct == NULL) {
223 				*aacct = malloc((unsigned) strlen(tokval) + 1);
224 				(void) strcpy(*aacct, tokval);
225 			}
226 			break;
227 		case MACDEF:
228 			while ((c=getc(cfile)) != EOF &&
229 						(c == ' ' || c == '\t'))
230 				;
231 			if (c == EOF || c == '\n') {
232 				printf("Missing macdef name argument.\n");
233 				goto bad;
234 			}
235 			if (macnum == 16) {
236 				printf("Limit of 16 macros have already been defined\n");
237 				goto bad;
238 			}
239 			tmp = macros[macnum].mac_name;
240 			*tmp++ = c;
241 			for (i=0; i < 8 && (c=getc(cfile)) != EOF &&
242 			    !isspace(c); ++i) {
243 				*tmp++ = c;
244 			}
245 			if (c == EOF) {
246 				printf("Macro definition missing null line terminator.\n");
247 				goto bad;
248 			}
249 			*tmp = '\0';
250 			if (c != '\n') {
251 				while ((c=getc(cfile)) != EOF && c != '\n');
252 			}
253 			if (c == EOF) {
254 				printf("Macro definition missing null line terminator.\n");
255 				goto bad;
256 			}
257 			if (macnum == 0) {
258 				macros[macnum].mac_start = macbuf;
259 			}
260 			else {
261 				macros[macnum].mac_start = macros[macnum-1].mac_end + 1;
262 			}
263 			tmp = macros[macnum].mac_start;
264 			while (tmp != macbuf + 4096) {
265 				if ((c=getc(cfile)) == EOF) {
266 				printf("Macro definition missing null line terminator.\n");
267 					goto bad;
268 				}
269 				*tmp = c;
270 				if (*tmp == '\n') {
271 					if (*(tmp-1) == '\0') {
272 					   macros[macnum++].mac_end = tmp - 1;
273 					   break;
274 					}
275 					*tmp = '\0';
276 				}
277 				tmp++;
278 			}
279 			if (tmp == macbuf + 4096) {
280 				printf("4K macro buffer exceeded\n");
281 				goto bad;
282 			}
283 			break;
284 		default:
285 			warnx("Unknown .netrc keyword %s", tokval);
286 			break;
287 		}
288 		goto done;
289 	}
290 done:
291 	(void) fclose(cfile);
292 	return (0);
293 bad:
294 	(void) fclose(cfile);
295 	return (-1);
296 }
297 
298 int
299 rexec_af(char **ahost, int rport, const char *name, const char *pass,
300     const char *cmd, int *fd2p, sa_family_t *af)
301 {
302 	struct sockaddr_storage sa2, from;
303 	struct addrinfo hints, *res0;
304 	const char *orig_name = name;
305 	const char *orig_pass = pass;
306 	static char *ahostbuf;
307 	u_short port = 0;
308 	int s, timo = 1, s3;
309 	char c;
310 	int gai;
311 	char servbuff[NI_MAXSERV];
312 
313 	snprintf(servbuff, sizeof(servbuff), "%d", ntohs(rport));
314 	servbuff[sizeof(servbuff) - 1] = '\0';
315 
316 	memset(&hints, '\0', sizeof(hints));
317 	if (af)
318 		hints.ai_family = *af;
319 	hints.ai_socktype = SOCK_STREAM;
320 	hints.ai_flags = AI_CANONNAME;
321 	gai = getaddrinfo(*ahost, servbuff, &hints, &res0);
322 	if (gai){
323 		/* XXX: set errno? */
324 		return -1;
325 	}
326 
327 	if (res0->ai_canonname){
328 		free (ahostbuf);
329 		ahostbuf = strdup (res0->ai_canonname);
330 		if (ahostbuf == NULL) {
331 			perror ("rexec: strdup");
332 			return (-1);
333 		}
334 		*ahost = ahostbuf;
335 	} else {
336 		*ahost = NULL;
337 		__set_errno (ENOENT);
338 		return -1;
339 	}
340 	ruserpass(res0->ai_canonname, &name, &pass, 0);
341 retry:
342 	s = socket(res0->ai_family, res0->ai_socktype, 0);
343 	if (s < 0) {
344 		perror("rexec: socket");
345 		return (-1);
346 	}
347 	if (connect(s, res0->ai_addr, res0->ai_addrlen) < 0) {
348 		if (errno == ECONNREFUSED && timo <= 16) {
349 			(void) close(s);
350 			sleep(timo);
351 			timo *= 2;
352 			goto retry;
353 		}
354 		perror(res0->ai_canonname);
355 		return (-1);
356 	}
357 	if (fd2p == NULL) {
358 		(void) write(s, "", 1);
359 		port = 0;
360 	} else {
361 		char num[32];
362 		int s2;
363 		socklen_t sa2len;
364 
365 		s2 = socket(res0->ai_family, res0->ai_socktype, 0);
366 		if (s2 < 0) {
367 			(void) close(s);
368 			return (-1);
369 		}
370 		listen(s2, 1);
371 		sa2len = sizeof (sa2);
372 		if (getsockname(s2, (struct sockaddr *)&sa2, &sa2len) < 0) {
373 			perror("getsockname");
374 			(void) close(s2);
375 			goto bad;
376 		} else if (sa2len != SA_LEN((struct sockaddr *)&sa2)) {
377 			__set_errno(EINVAL);
378 			(void) close(s2);
379 			goto bad;
380 		}
381 		port = 0;
382 		if (!getnameinfo((struct sockaddr *)&sa2, sa2len,
383 				 NULL, 0, servbuff, sizeof(servbuff),
384 				 NI_NUMERICSERV))
385 			port = atoi(servbuff);
386 		(void) sprintf(num, "%u", port);
387 		(void) write(s, num, strlen(num)+1);
388 		{ socklen_t len = sizeof (from);
389 		  s3 = accept(s2, (struct sockaddr *)&from,
390 						  &len);
391 		  close(s2);
392 		  if (s3 < 0) {
393 			perror("accept");
394 			port = 0;
395 			goto bad;
396 		  }
397 		}
398 		*fd2p = s3;
399 	}
400 
401 	(void) write(s, name, strlen(name) + 1);
402 	/* should public key encypt the password here */
403 	(void) write(s, pass, strlen(pass) + 1);
404 	(void) write(s, cmd, strlen(cmd) + 1);
405 
406 	/* We don't need the memory allocated for the name and the password
407 	   in ruserpass anymore.  */
408 	if (name != orig_name)
409 	  free ((char *) name);
410 	if (pass != orig_pass)
411 	  free ((char *) pass);
412 
413 	if (read(s, &c, 1) != 1) {
414 		perror(*ahost);
415 		goto bad;
416 	}
417 	if (c != 0) {
418 		while (read(s, &c, 1) == 1) {
419 			(void) write(2, &c, 1);
420 			if (c == '\n')
421 				break;
422 		}
423 		goto bad;
424 	}
425 	freeaddrinfo(res0);
426 	return (s);
427 bad:
428 	if (port)
429 		(void) close(*fd2p);
430 	(void) close(s);
431 	freeaddrinfo(res0);
432 	return (-1);
433 }
434 
435 
436 int
437 rexec(char **ahost, int rport, const char *name, const char *pass, char *cmd, int *fd2p)
438 {
439 	struct sockaddr_in sin, sin2, from;
440 	struct hostent *hp;
441 	u_short port;
442 	int s, timo = 1, s3;
443 	char c;
444 	char *acct = NULL;
445 
446 	hp = gethostbyname(*ahost);
447 	if (hp == NULL) {
448 		herror(*ahost);
449 		return (-1);
450 	}
451 	*ahost = hp->h_name;
452 	ruserpass(hp->h_name, &name, &pass, &acct);
453 	if (acct != NULL)
454 		free(acct);
455 retry:
456 	s = socket(AF_INET, SOCK_STREAM, 0);
457 	if (s < 0) {
458 		perror("rexec: socket");
459 		return (-1);
460 	}
461 	sin.sin_family = hp->h_addrtype;
462 	sin.sin_port = rport;
463 	bcopy(hp->h_addr, (caddr_t)&sin.sin_addr, hp->h_length);
464 	if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
465 		if (errno == ECONNREFUSED && timo <= 16) {
466 			(void) close(s);
467 			sleep(timo);
468 			timo *= 2;
469 			goto retry;
470 		}
471 		perror(hp->h_name);
472 		return (-1);
473 	}
474 	if (fd2p == NULL) {
475 		(void) write(s, "", 1);
476 		port = 0;
477 	} else {
478 		char num[8];
479 		int s2, sin2len;
480 
481 		s2 = socket(AF_INET, SOCK_STREAM, 0);
482 		if (s2 < 0) {
483 			(void) close(s);
484 			return (-1);
485 		}
486 		listen(s2, 1);
487 		sin2len = sizeof (sin2);
488 		if (getsockname(s2, (struct sockaddr *)&sin2, &sin2len) < 0 ||
489 		  sin2len != sizeof (sin2)) {
490 			perror("getsockname");
491 			(void) close(s2);
492 			goto bad;
493 		}
494 		port = ntohs((u_short)sin2.sin_port);
495 		(void) sprintf(num, "%hu", port);
496 		(void) write(s, num, strlen(num)+1);
497 		{ int len = sizeof (from);
498 		  s3 = accept(s2, (struct sockaddr *)&from, &len);
499 		  close(s2);
500 		  if (s3 < 0) {
501 			perror("accept");
502 			port = 0;
503 			goto bad;
504 		  }
505 		}
506 		*fd2p = s3;
507 	}
508 	(void) write(s, name, strlen(name) + 1);
509 	/* should public key encypt the password here */
510 	(void) write(s, pass, strlen(pass) + 1);
511 	(void) write(s, cmd, strlen(cmd) + 1);
512 	if (read(s, &c, 1) != 1) {
513 		perror(*ahost);
514 		goto bad;
515 	}
516 	if (c != 0) {
517 		while (read(s, &c, 1) == 1) {
518 			(void) write(2, &c, 1);
519 			if (c == '\n')
520 				break;
521 		}
522 		goto bad;
523 	}
524 	return (s);
525 bad:
526 	if (port)
527 		(void) close(*fd2p);
528 	(void) close(s);
529 	return (-1);
530 }
531