xref: /netbsd-src/usr.sbin/lpr/common_source/rmjob.c (revision fdecd6a253f999ae92b139670d9e15cc9df4497c)
1 /*	$NetBSD: rmjob.c,v 1.11 1997/07/10 06:19:54 mikel Exp $	*/
2 
3 /*
4  * Copyright (c) 1983, 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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)rmjob.c	8.1 (Berkeley) 6/6/93";
39 #else
40 static char rcsid[] = "$NetBSD";
41 #endif
42 #endif /* not lint */
43 
44 #include <sys/param.h>
45 
46 #include <signal.h>
47 #include <errno.h>
48 #include <dirent.h>
49 #include <unistd.h>
50 #include <stdlib.h>
51 #include <stdio.h>
52 #include <string.h>
53 #include <ctype.h>
54 #include "lp.h"
55 #include "lp.local.h"
56 #include "pathnames.h"
57 
58 /*
59  * rmjob - remove the specified jobs from the queue.
60  */
61 
62 /*
63  * Stuff for handling lprm specifications
64  */
65 extern char	*user[];		/* users to process */
66 extern int	users;			/* # of users in user array */
67 extern int	requ[];			/* job number of spool entries */
68 extern int	requests;		/* # of spool requests */
69 extern char	*person;		/* name of person doing lprm */
70 
71 static char	root[] = "root";
72 static int	all = 0;		/* eliminate all files (root only) */
73 static int	cur_daemon;		/* daemon's pid */
74 static char	current[40];		/* active control file name */
75 
76 extern uid_t	uid, euid;		/* real and effective user id's */
77 
78 static	void	do_unlink __P((char *));
79 
80 void
81 rmjob()
82 {
83 	register int i, nitems;
84 	int assasinated = 0;
85 	struct dirent **files;
86 	char *cp;
87 
88 	if ((i = cgetent(&bp, printcapdb, printer)) == -2)
89 		fatal("can't open printer description file");
90 	else if (i == -1)
91 		fatal("unknown printer");
92 	else if (i == -3)
93 		fatal("potential reference loop detected in printcap file");
94 	if (cgetstr(bp, "lp", &LP) < 0)
95 		LP = _PATH_DEFDEVLP;
96 	if (cgetstr(bp, "rp", &RP) < 0)
97 		RP = DEFLP;
98 	if (cgetstr(bp, "sd", &SD) < 0)
99 		SD = _PATH_DEFSPOOL;
100 	if (cgetstr(bp,"lo", &LO) < 0)
101 		LO = DEFLOCK;
102 	cgetstr(bp, "rm", &RM);
103 	if ((cp = checkremote()) != NULL)
104 		printf("Warning: %s\n", cp);
105 
106 	/*
107 	 * If the format was `lprm -' and the user isn't the super-user,
108 	 *  then fake things to look like he said `lprm user'.
109 	 */
110 	if (users < 0) {
111 		if (getuid() == 0)
112 			all = 1;	/* all files in local queue */
113 		else {
114 			user[0] = person;
115 			users = 1;
116 		}
117 	}
118 	if (!strcmp(person, "-all")) {
119 		if (from == host)
120 			fatal("The login name \"-all\" is reserved");
121 		all = 1;	/* all those from 'from' */
122 		person = root;
123 	}
124 
125 	seteuid(euid);
126 	if (chdir(SD) < 0)
127 		fatal("cannot chdir to spool directory");
128 	if ((nitems = scandir(".", &files, iscf, NULL)) < 0)
129 		fatal("cannot access spool directory");
130 	seteuid(uid);
131 
132 	if (nitems) {
133 		/*
134 		 * Check for an active printer daemon (in which case we
135 		 *  kill it if it is reading our file) then remove stuff
136 		 *  (after which we have to restart the daemon).
137 		 */
138 		if (lockchk(LO) && chk(current)) {
139 			seteuid(euid);
140 			assasinated = kill(cur_daemon, SIGINT) == 0;
141 			seteuid(uid);
142 			if (!assasinated)
143 				fatal("cannot kill printer daemon");
144 		}
145 		/*
146 		 * process the files
147 		 */
148 		for (i = 0; i < nitems; i++)
149 			process(files[i]->d_name);
150 	}
151 	rmremote();
152 	/*
153 	 * Restart the printer daemon if it was killed
154 	 */
155 	if (assasinated && !startdaemon(printer))
156 		fatal("cannot restart printer daemon\n");
157 	exit(0);
158 }
159 
160 /*
161  * Process a lock file: collect the pid of the active
162  *  daemon and the file name of the active spool entry.
163  * Return boolean indicating existence of a lock file.
164  */
165 int
166 lockchk(s)
167 	char *s;
168 {
169 	register FILE *fp;
170 	register int i, n;
171 
172 	seteuid(euid);
173 	if ((fp = fopen(s, "r")) == NULL) {
174 		if (errno == EACCES)
175 			fatal("can't access lock file");
176 		else
177 			return(0);
178 	}
179 	seteuid(uid);
180 	if (!getline(fp)) {
181 		(void)fclose(fp);
182 		return(0);		/* no daemon present */
183 	}
184 	cur_daemon = atoi(line);
185 	if (kill(cur_daemon, 0) < 0 && errno != EPERM) {
186 		(void)fclose(fp);
187 		return(0);		/* no daemon present */
188 	}
189 	for (i = 1; (n = fread(current, sizeof(char), sizeof(current), fp)) <= 0; i++) {
190 		if (i > 5) {
191 			n = 1;
192 			break;
193 		}
194 		sleep(i);
195 	}
196 	current[n-1] = '\0';
197 	(void)fclose(fp);
198 	return(1);
199 }
200 
201 /*
202  * Process a control file.
203  */
204 void
205 process(file)
206 	char *file;
207 {
208 	FILE *cfp;
209 
210 	if (!chk(file))
211 		return;
212 	seteuid(euid);
213 	if ((cfp = fopen(file, "r")) == NULL)
214 		fatal("cannot open %s", file);
215 	seteuid(uid);
216 	while (getline(cfp)) {
217 		switch (line[0]) {
218 		case 'U':  /* unlink associated files */
219 			do_unlink(line+1);
220 		}
221 	}
222 	(void)fclose(cfp);
223 	do_unlink(file);
224 }
225 
226 static void
227 do_unlink(file)
228 	char *file;
229 {
230 	int	ret;
231 
232 	if (from != host)
233 		printf("%s: ", host);
234 	seteuid(euid);
235 	ret = unlink(file);
236 	seteuid(uid);
237 	printf(ret ? "cannot dequeue %s\n" : "%s dequeued\n", file);
238 }
239 
240 /*
241  * Do the dirty work in checking
242  */
243 int
244 chk(file)
245 	char *file;
246 {
247 	register int *r, n;
248 	register char **u, *cp;
249 	FILE *cfp;
250 
251 	/*
252 	 * Check for valid cf file name (mostly checking current).
253 	 */
254 	if (strlen(file) < 7 || file[0] != 'c' || file[1] != 'f')
255 		return(0);
256 
257 	if (all && (from == host || !strcmp(from, file+6)))
258 		return(1);
259 
260 	/*
261 	 * get the owner's name from the control file.
262 	 */
263 	seteuid(euid);
264 	if ((cfp = fopen(file, "r")) == NULL)
265 		return(0);
266 	seteuid(uid);
267 	while (getline(cfp)) {
268 		if (line[0] == 'P')
269 			break;
270 	}
271 	(void)fclose(cfp);
272 	if (line[0] != 'P')
273 		return(0);
274 
275 	if (users == 0 && requests == 0)
276 		return(!strcmp(file, current) && isowner(line+1, file));
277 	/*
278 	 * Check the request list
279 	 */
280 	for (n = 0, cp = file+3; isdigit(*cp); )
281 		n = n * 10 + (*cp++ - '0');
282 	for (r = requ; r < &requ[requests]; r++)
283 		if (*r == n && isowner(line+1, file))
284 			return(1);
285 	/*
286 	 * Check to see if it's in the user list
287 	 */
288 	for (u = user; u < &user[users]; u++)
289 		if (!strcmp(*u, line+1) && isowner(line+1, file))
290 			return(1);
291 	return(0);
292 }
293 
294 /*
295  * If root is removing a file on the local machine, allow it.
296  * If root is removing a file from a remote machine, only allow
297  * files sent from the remote machine to be removed.
298  * Normal users can only remove the file from where it was sent.
299  */
300 int
301 isowner(owner, file)
302 	char *owner, *file;
303 {
304 	if (!strcmp(person, root) && (from == host || !strcmp(from, file+6)))
305 		return(1);
306 	if (!strcmp(person, owner) && !strcmp(from, file+6))
307 		return(1);
308 	if (from != host)
309 		printf("%s: ", host);
310 	printf("%s: Permission denied\n", file);
311 	return(0);
312 }
313 
314 /*
315  * Check to see if we are sending files to a remote machine. If we are,
316  * then try removing files on the remote machine.
317  */
318 void
319 rmremote()
320 {
321 	register char *cp, *s;
322 	register int i, rem, len;
323 
324 	if (!sendtorem)
325 		return;	/* not sending to a remote machine */
326 
327 	/*
328 	 * Flush stdout so the user can see what has been deleted
329 	 * while we wait (possibly) for the connection.
330 	 */
331 	fflush(stdout);
332 
333 	/* \5 RP space all */
334 	len = 1 + strlen(RP) + 1 + strlen(all ? "-all" : person);
335 	for (i = 0; i < users; i++) {
336 		len += strlen(user[i]) + 1;
337 	}
338 	for (i = 0; i < requests; i++) {
339 		len += snprintf(line, sizeof(line), " %d", requ[i]);
340 	}
341 	/* newline nul */
342 	len += 2;
343 	if (len > sizeof(line))
344 		s = malloc(len);
345 	else
346 		s = line;
347 	cp = s;
348 
349 	cp += snprintf(s, len, "\5%s %s", RP, all ? "-all" : person);
350 	for (i = 0; i < users; i++) {
351 		*cp++ = ' ';
352 		strncpy(cp, user[i], len - (cp - s) - 2);
353 		cp += strlen(cp);
354 	}
355 	for (i = 0; i < requests; i++) {
356 		(void)snprintf(cp, len - (cp - s) - 1, " %d", requ[i]);
357 		cp += strlen(cp);
358 	}
359 	cp[0] = '\n';
360 	cp[1] = '\0';
361 
362 	rem = getport(RM);
363 	if (rem < 0) {
364 		if (from != host)
365 			printf("%s: ", host);
366 		printf("connection to %s is down\n", RM);
367 	} else {
368 		if (write(rem, s, len) != len)
369 			fatal("Lost connection");
370 		if (len > sizeof(line))
371 			(void)free(s);
372 		while ((i = read(rem, line, sizeof(line))) > 0)
373 			(void)fwrite(line, 1, i, stdout);
374 		(void)close(rem);
375 	}
376 }
377 
378 /*
379  * Return 1 if the filename begins with 'cf'
380  */
381 int
382 iscf(d)
383 	struct dirent *d;
384 {
385 	return(d->d_name[0] == 'c' && d->d_name[1] == 'f');
386 }
387