xref: /freebsd/lib/libcompat/4.3/rexec.c (revision 4f52dfbb8d6c4d446500c5b097e3806ec219fbd4)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1980, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  * $FreeBSD$
32  */
33 
34 #if defined(LIBC_SCCS) && !defined(lint)
35 static char sccsid[] = "@(#)rexec.c	8.1 (Berkeley) 6/4/93";
36 #endif /* LIBC_SCCS and not lint */
37 
38 #include <sys/types.h>
39 #include <sys/uio.h>
40 #include <sys/socket.h>
41 #include <sys/param.h>
42 #include <sys/stat.h>
43 
44 #include <netinet/in.h>
45 
46 #include <stdio.h>
47 #include <unistd.h>
48 #include <string.h>
49 #include <netdb.h>
50 #include <errno.h>
51 #include <ctype.h>
52 #include <err.h>
53 #include <stdlib.h>
54 #include <unistd.h>
55 
56 int	rexecoptions;
57 char	*getpass(), *getlogin();
58 
59 /*
60  * Options and other state info.
61  */
62 struct macel {
63 	char mac_name[9];	/* macro name */
64 	char *mac_start;	/* start of macro in macbuf */
65 	char *mac_end;		/* end of macro in macbuf */
66 };
67 
68 int macnum;			/* number of defined macros */
69 struct macel macros[16];
70 char macbuf[4096];
71 
72 static	FILE *cfile;
73 
74 #define	DEFAULT	1
75 #define	LOGIN	2
76 #define	PASSWD	3
77 #define	ACCOUNT 4
78 #define MACDEF  5
79 #define	ID	10
80 #define	MACH	11
81 
82 static char tokval[100];
83 
84 static struct toktab {
85 	char *tokstr;
86 	int tval;
87 } toktab[]= {
88 	{ "default",	DEFAULT },
89 	{ "login",	LOGIN },
90 	{ "password",	PASSWD },
91 	{ "passwd",	PASSWD },
92 	{ "account",	ACCOUNT },
93 	{ "machine",	MACH },
94 	{ "macdef",	MACDEF },
95 	{ NULL,		0 }
96 };
97 
98 static int
99 token()
100 {
101 	char *cp;
102 	int c;
103 	struct toktab *t;
104 
105 	if (feof(cfile) || ferror(cfile))
106 		return (0);
107 	while ((c = getc(cfile)) != EOF &&
108 	    (c == '\n' || c == '\t' || c == ' ' || c == ','))
109 		continue;
110 	if (c == EOF)
111 		return (0);
112 	cp = tokval;
113 	if (c == '"') {
114 		while ((c = getc(cfile)) != EOF && c != '"') {
115 			if (c == '\\')
116 				c = getc(cfile);
117 			*cp++ = c;
118 		}
119 	} else {
120 		*cp++ = c;
121 		while ((c = getc(cfile)) != EOF
122 		    && c != '\n' && c != '\t' && c != ' ' && c != ',') {
123 			if (c == '\\')
124 				c = getc(cfile);
125 			*cp++ = c;
126 		}
127 	}
128 	*cp = 0;
129 	if (tokval[0] == 0)
130 		return (0);
131 	for (t = toktab; t->tokstr; t++)
132 		if (!strcmp(t->tokstr, tokval))
133 			return (t->tval);
134 	return (ID);
135 }
136 
137 static int
138 ruserpass(host, aname, apass, aacct)
139 	char *host, **aname, **apass, **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 					*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 == 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 				*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 == NULL) {
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(ahost, rport, name, pass, cmd, fd2p)
298 	char **ahost;
299 	int rport;
300 	char *name, *pass, *cmd;
301 	int *fd2p;
302 {
303 	struct sockaddr_in sin, sin2, from;
304 	struct hostent *hp;
305 	u_short port;
306 	int s, timo = 1, s3;
307 	char c, *acct;
308 
309 	hp = gethostbyname(*ahost);
310 	if (hp == NULL) {
311 		herror(*ahost);
312 		return (-1);
313 	}
314 	*ahost = hp->h_name;
315 	acct = NULL;
316 	ruserpass(hp->h_name, &name, &pass, &acct);
317 	free(acct);
318 retry:
319 	s = socket(AF_INET, SOCK_STREAM, 0);
320 	if (s < 0) {
321 		perror("rexec: socket");
322 		return (-1);
323 	}
324 	sin.sin_family = hp->h_addrtype;
325 	sin.sin_port = rport;
326 	bcopy(hp->h_addr, (caddr_t)&sin.sin_addr, hp->h_length);
327 	if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
328 		if (errno == ECONNREFUSED && timo <= 16) {
329 			(void) close(s);
330 			sleep(timo);
331 			timo *= 2;
332 			goto retry;
333 		}
334 		perror(hp->h_name);
335 		(void) close(s);
336 		return (-1);
337 	}
338 	port = 0;
339 	if (fd2p == 0)
340 		(void) write(s, "", 1);
341 	else {
342 		char num[8];
343 		int s2, sin2len;
344 
345 		s2 = socket(AF_INET, SOCK_STREAM, 0);
346 		if (s2 < 0) {
347 			(void) close(s);
348 			return (-1);
349 		}
350 		listen(s2, 1);
351 		sin2len = sizeof (sin2);
352 		if (getsockname(s2, (struct sockaddr *)&sin2, &sin2len) < 0 ||
353 		  sin2len != sizeof (sin2)) {
354 			perror("getsockname");
355 			(void) close(s2);
356 			goto bad;
357 		}
358 		port = ntohs((u_short)sin2.sin_port);
359 		(void) sprintf(num, "%hu", port);
360 		(void) write(s, num, strlen(num)+1);
361 		{ int len = sizeof (from);
362 		  s3 = accept(s2, (struct sockaddr *)&from, &len);
363 		  close(s2);
364 		  if (s3 < 0) {
365 			perror("accept");
366 			port = 0;
367 			goto bad;
368 		  }
369 		}
370 		*fd2p = s3;
371 	}
372 	(void) write(s, name, strlen(name) + 1);
373 	/* should public key encypt the password here */
374 	(void) write(s, pass, strlen(pass) + 1);
375 	(void) write(s, cmd, strlen(cmd) + 1);
376 	if (read(s, &c, 1) != 1) {
377 		perror(*ahost);
378 		goto bad;
379 	}
380 	if (c != 0) {
381 		while (read(s, &c, 1) == 1) {
382 			(void) write(2, &c, 1);
383 			if (c == '\n')
384 				break;
385 		}
386 		goto bad;
387 	}
388 	return (s);
389 bad:
390 	if (port)
391 		(void) close(*fd2p);
392 	(void) close(s);
393 	return (-1);
394 }
395