xref: /freebsd/usr.sbin/lpr/common_source/rmjob.c (revision 0de89efe5c443f213c7ea28773ef2dc6cf3af2ed)
1 /*
2  * Copyright (c) 1983, 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 
34 #ifndef lint
35 #if 0
36 static char sccsid[] = "@(#)rmjob.c	8.2 (Berkeley) 4/28/95";
37 #endif
38 static const char rcsid[] =
39 	"$Id$";
40 #endif /* not lint */
41 
42 #include <sys/param.h>
43 
44 #include <signal.h>
45 #include <errno.h>
46 #include <dirent.h>
47 #include <unistd.h>
48 #include <stdlib.h>
49 #include <stdio.h>
50 #include <string.h>
51 #include <ctype.h>
52 #include "lp.h"
53 #include "lp.local.h"
54 #include "pathnames.h"
55 
56 /*
57  * rmjob - remove the specified jobs from the queue.
58  */
59 
60 /*
61  * Stuff for handling lprm specifications
62  */
63 static char	root[] = "root";
64 static int	all = 0;		/* eliminate all files (root only) */
65 static int	cur_daemon;		/* daemon's pid */
66 static char	current[40];		/* active control file name */
67 
68 extern uid_t	uid, euid;		/* real and effective user id's */
69 
70 static	void	do_unlink __P((char *));
71 
72 void
73 rmjob()
74 {
75 	register int i, nitems;
76 	int assasinated = 0;
77 	struct dirent **files;
78 	char *cp;
79 
80 	if ((i = cgetent(&bp, printcapdb, printer)) == -2)
81 		fatal("can't open printer description file");
82 	else if (i == -1)
83 		fatal("unknown printer");
84 	else if (i == -3)
85 		fatal("potential reference loop detected in printcap file");
86 	if (cgetstr(bp, "lp", &LP) < 0)
87 		LP = _PATH_DEFDEVLP;
88 	if (cgetstr(bp, "rp", &RP) < 0)
89 		RP = DEFLP;
90 	if (cgetstr(bp, "sd", &SD) < 0)
91 		SD = _PATH_DEFSPOOL;
92 	if (cgetstr(bp,"lo", &LO) < 0)
93 		LO = DEFLOCK;
94 	cgetstr(bp, "rm", &RM);
95 	if ((cp = checkremote()))
96 		printf("Warning: %s\n", cp);
97 
98 	/*
99 	 * If the format was `lprm -' and the user isn't the super-user,
100 	 *  then fake things to look like he said `lprm user'.
101 	 */
102 	if (users < 0) {
103 		if (getuid() == 0)
104 			all = 1;	/* all files in local queue */
105 		else {
106 			user[0] = person;
107 			users = 1;
108 		}
109 	}
110 	if (!strcmp(person, "-all")) {
111 		if (from == host)
112 			fatal("The login name \"-all\" is reserved");
113 		all = 1;	/* all those from 'from' */
114 		person = root;
115 	}
116 
117 	seteuid(euid);
118 	if (chdir(SD) < 0)
119 		fatal("cannot chdir to spool directory");
120 	if ((nitems = scandir(".", &files, iscf, NULL)) < 0)
121 		fatal("cannot access spool directory");
122 	seteuid(uid);
123 
124 	if (nitems) {
125 		/*
126 		 * Check for an active printer daemon (in which case we
127 		 *  kill it if it is reading our file) then remove stuff
128 		 *  (after which we have to restart the daemon).
129 		 */
130 		if (lockchk(LO) && chk(current)) {
131 			seteuid(euid);
132 			assasinated = kill(cur_daemon, SIGINT) == 0;
133 			seteuid(uid);
134 			if (!assasinated)
135 				fatal("cannot kill printer daemon");
136 		}
137 		/*
138 		 * process the files
139 		 */
140 		for (i = 0; i < nitems; i++)
141 			process(files[i]->d_name);
142 	}
143 	rmremote();
144 	/*
145 	 * Restart the printer daemon if it was killed
146 	 */
147 	if (assasinated && !startdaemon(printer))
148 		fatal("cannot restart printer daemon\n");
149 	exit(0);
150 }
151 
152 /*
153  * Process a lock file: collect the pid of the active
154  *  daemon and the file name of the active spool entry.
155  * Return boolean indicating existence of a lock file.
156  */
157 int
158 lockchk(s)
159 	char *s;
160 {
161 	register FILE *fp;
162 	register int i, n;
163 
164 	seteuid(euid);
165 	if ((fp = fopen(s, "r")) == NULL) {
166 		if (errno == EACCES)
167 			fatal("can't access lock file");
168 		else
169 			return(0);
170 	}
171 	seteuid(uid);
172 	if (!getline(fp)) {
173 		(void) fclose(fp);
174 		return(0);		/* no daemon present */
175 	}
176 	cur_daemon = atoi(line);
177 	if (kill(cur_daemon, 0) < 0 && errno != EPERM) {
178 		(void) fclose(fp);
179 		return(0);		/* no daemon present */
180 	}
181 	for (i = 1; (n = fread(current, sizeof(char), sizeof(current), fp)) <= 0; i++) {
182 		if (i > 5) {
183 			n = 1;
184 			break;
185 		}
186 		sleep(i);
187 	}
188 	current[n-1] = '\0';
189 	(void) fclose(fp);
190 	return(1);
191 }
192 
193 /*
194  * Process a control file.
195  */
196 void
197 process(file)
198 	char *file;
199 {
200 	FILE *cfp;
201 
202 	if (!chk(file))
203 		return;
204 	seteuid(euid);
205 	if ((cfp = fopen(file, "r")) == NULL)
206 		fatal("cannot open %s", file);
207 	seteuid(uid);
208 	while (getline(cfp)) {
209 		switch (line[0]) {
210 		case 'U':  /* unlink associated files */
211 			if (strchr(line+1, '/') || strncmp(line+1, "df", 2))
212 				break;
213 			if (from != host)
214 				printf("%s: ", host);
215 			do_unlink(line+1);
216 		}
217 	}
218 	(void) fclose(cfp);
219 	do_unlink(file);
220 }
221 
222 static void
223 do_unlink(file)
224 	char *file;
225 {
226 	int	ret;
227 
228 	if (from != host)
229 		printf("%s: ", host);
230 	seteuid(euid);
231 	ret = unlink(file);
232 	seteuid(uid);
233 	printf(ret ? "cannot dequeue %s\n" : "%s dequeued\n", file);
234 }
235 
236 /*
237  * Do the dirty work in checking
238  */
239 int
240 chk(file)
241 	char *file;
242 {
243 	register int *r, n;
244 	register char **u, *cp;
245 	FILE *cfp;
246 
247 	/*
248 	 * Check for valid cf file name (mostly checking current).
249 	 */
250 	if (strlen(file) < 7 || file[0] != 'c' || file[1] != 'f')
251 		return(0);
252 
253 	if (all && (from == host || !strcmp(from, file+6)))
254 		return(1);
255 
256 	/*
257 	 * get the owner's name from the control file.
258 	 */
259 	seteuid(euid);
260 	if ((cfp = fopen(file, "r")) == NULL)
261 		return(0);
262 	seteuid(uid);
263 	while (getline(cfp)) {
264 		if (line[0] == 'P')
265 			break;
266 	}
267 	(void) fclose(cfp);
268 	if (line[0] != 'P')
269 		return(0);
270 
271 	if (users == 0 && requests == 0)
272 		return(!strcmp(file, current) && isowner(line+1, file));
273 	/*
274 	 * Check the request list
275 	 */
276 	for (n = 0, cp = file+3; isdigit(*cp); )
277 		n = n * 10 + (*cp++ - '0');
278 	for (r = requ; r < &requ[requests]; r++)
279 		if (*r == n && isowner(line+1, file))
280 			return(1);
281 	/*
282 	 * Check to see if it's in the user list
283 	 */
284 	for (u = user; u < &user[users]; u++)
285 		if (!strcmp(*u, line+1) && isowner(line+1, file))
286 			return(1);
287 	return(0);
288 }
289 
290 /*
291  * If root is removing a file on the local machine, allow it.
292  * If root is removing a file from a remote machine, only allow
293  * files sent from the remote machine to be removed.
294  * Normal users can only remove the file from where it was sent.
295  */
296 int
297 isowner(owner, file)
298 	char *owner, *file;
299 {
300 	if (!strcmp(person, root) && (from == host || !strcmp(from, file+6)))
301 		return(1);
302 	if (!strcmp(person, owner) && !strcmp(from, file+6))
303 		return(1);
304 	if (from != host)
305 		printf("%s: ", host);
306 	printf("%s: Permission denied\n", file);
307 	return(0);
308 }
309 
310 /*
311  * Check to see if we are sending files to a remote machine. If we are,
312  * then try removing files on the remote machine.
313  */
314 void
315 rmremote()
316 {
317 	register char *cp;
318 	register int i, rem;
319 	char buf[BUFSIZ];
320 
321 	if (!remote)
322 		return;	/* not sending to a remote machine */
323 
324 	/*
325 	 * Flush stdout so the user can see what has been deleted
326 	 * while we wait (possibly) for the connection.
327 	 */
328 	fflush(stdout);
329 
330 	(void)snprintf(buf, sizeof(buf), "\5%s %s", RP, all ? "-all" : person);
331 	cp = buf;
332 	for (i = 0; i < users && cp-buf+1+strlen(user[i]) < sizeof(buf); i++) {
333 		cp += strlen(cp);
334 		*cp++ = ' ';
335 		strcpy(cp, user[i]);
336 	}
337 	for (i = 0; i < requests && cp-buf+10 < sizeof(buf) - 1; i++) {
338 		cp += strlen(cp);
339 		(void) sprintf(cp, " %d", requ[i]);
340 	}
341 	strcat(cp, "\n");
342 	rem = getport(RM, 0);
343 	if (rem < 0) {
344 		if (from != host)
345 			printf("%s: ", host);
346 		printf("connection to %s is down\n", RM);
347 	} else {
348 		i = strlen(buf);
349 		if (write(rem, buf, i) != i)
350 			fatal("Lost connection");
351 		while ((i = read(rem, buf, sizeof(buf))) > 0)
352 			(void) fwrite(buf, 1, i, stdout);
353 		(void) close(rem);
354 	}
355 }
356 
357 /*
358  * Return 1 if the filename begins with 'cf'
359  */
360 int
361 iscf(d)
362 	struct dirent *d;
363 {
364 	return(d->d_name[0] == 'c' && d->d_name[1] == 'f');
365 }
366